subject:(dioxygen)

University of Illinois – Urbana-Champaign

1. Thorseth, Matthew. Electrocatalytic dioxygen reduction with copper complexes.

Degree: PhD, 0335, 2012, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/31948

► The oxygen reduction reaction (ORR) is the four electron and four proton reaction with oxygen to form water. This reaction, while very exothermic (-474 kJ/mol),… (more)

▼ The oxygen reduction reaction (ORR) is the four electron and four proton reaction with oxygen to form water. This reaction, while very exothermic (-474 kJ/mol), remains a difficult reaction to harness due to the high O-O bond strength (485 kJ). Many proteins in nature couple the ORR to various substrate oxidations in order to provide energy, such as in respiration. Commercially, the ORR is important in a large number of systems, chiefly as the cathode reaction in a polymer electrolyte membrane fuel cell (PEMFC). While fuel cells have been in use since in their modern form since the 1960s, they are still not widely employed. The main factor preventing fuel cell proliferation is the high overpotentials for the ORR, the cathode reaction. Cathodes are typically constructed with Pt based catalysts, which exhibit ~300 mV of overpotential, leading to high loading of Pt and therefore large costs for the fuel cell stack. Using Nature as an inspiration, this dissertation explores the fundamental reaction mechanism of the oxygen reduction reaction as electrocatalyzed by copper complexes. The second chapter focuses on two similar complexes, [CuTPA]2+ (TPA = tris(2-pyridylmethyl)amine) and [Cu2bistripic]2+ (bistripic = 1,2-bis(6-(bis(6-methylpyridin-2-yl)methyl)pyridin-2-yl)ethane). CuTPA reacts with dioxygen to form an end-on peroxo complex, while Cu2bistripic forms a side-on peroxo complex. It is found that both complexes likely react to form Cu2O2 complexes, with CuTPA exhibiting lower overpotentials for the ORR than Cu2bistripic. The low overpotential for the ORR by [CuTPA]2+ is attributed to the nucleophilicity of the end-on peroxo species, while the high overpotential for [Cu2bistripic]2+ and the side-on peroxo complex, is due to its electrophilicity. Attempts at understanding the ligand effects on the ORR are studied in Chapter 3. Many ligands based on the CuTPA motif were studied. A series of ligands that raise the CuI/II couple potential are found to have no effect on the overpotential for the ORR. Similarly, addition of hydrogen-bonding groups did not effect on the overpotential. Ligands with only alkyl functionality exhibited very high overpotentials, which is attributed to poor electron transfer into the alkyl-Cu complex. The rate determining step (RDS) is not the CuII to CuI reduction, nor is it a protonation event. I speculate that the RDS is the reduction of a hydroperoxo intermediate. The first step in the ORR catalytic reaction mechanism for [CuTPA]2+ is examined in detail in Chapter 4. Using in-situ Raman spectroscopy, the initially electro-reduced CuTPA species is examined. Solution electrochemistry confirms that an insoluble species precipitates on the electrode surface upon a reduction of [CuTPA]2+. There is evidence that the reduced species is the cuprous complex, which then disproportionates into Cu metal and [CuTPA]2+. There also may be a hydrated perchlorate bridged species. The actual catalytically active species is cannot be readily identified, as the mixture of species is complex. Advisors/Committee Members: Gewirth, Andrew A. (advisor), Gewirth, Andrew A. (Committee Chair), Rauchfuss, Thomas B. (committee member), Girolami, Gregory S. (committee member), Suslick, Kenneth S. (committee member).

Subjects/Keywords: copper; dioxygen reduction; electrochemistry; catalysis

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APA (6^th Edition):

Thorseth, M. (2012). Electrocatalytic dioxygen reduction with copper complexes. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/31948

Chicago Manual of Style (16^th Edition):

Thorseth, Matthew. “Electrocatalytic dioxygen reduction with copper complexes.” 2012. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed March 08, 2021. http://hdl.handle.net/2142/31948.

MLA Handbook (7^th Edition):

Thorseth, Matthew. “Electrocatalytic dioxygen reduction with copper complexes.” 2012. Web. 08 Mar 2021.

Vancouver:

Thorseth M. Electrocatalytic dioxygen reduction with copper complexes. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2012. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2142/31948.

Council of Science Editors:

Thorseth M. Electrocatalytic dioxygen reduction with copper complexes. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2012. Available from: http://hdl.handle.net/2142/31948

Penn State University

2. Dassama, Laura Massah. Mechanistic Investigations of Class I Ribonucleotide Reductases and Related Oxygen-utilizing Metalloenzymes.

Degree: 2013, Penn State University

URL: https://submit-etda.libraries.psu.edu/catalog/17413

► Enzymes, nature’s preferred catalysts, often effect remarkable transformations of their substrates, and the mechanistic elucidation of these catalysts has significantly advanced our understanding of biological… (more)

▼ Enzymes, nature’s preferred catalysts, often effect remarkable transformations of their substrates, and the mechanistic elucidation of these catalysts has significantly advanced our understanding of biological processes. Our work is focuses on the detailed characterization of enzymes operating in an aerobic environment that utilize one or more transition metals as cofactors to facilitate transformation of their substrates. The approach of choice to facilitate the mechanistic elucidation of these enzymatic reactions involves the capture of transient species (reactive intermediates) that occur along each reaction sequence, and the kinetic and spectroscopic characterization of each captured species. A major focus of this thesis involves mechanistic investigations of a classic O2-utilizing metalloenzyme, ribonucleotide reductase (RNR). By catalyzing the conversion of ribonucleotides to deoxyribonucleotides [ND(T)Ps], RNRs provide all organisms with the required precursors for the de novo synthesis and repair of DNA. RNRs accomplish this chemically challenging feat with great fidelity by harnessing free-radical chemistry. To date, all RNRs characterized utilize an unstable cysteine thiyl radical (C•), formed in close proximity to the bound ND(T)P to initiate ribonucleotide reduction. Class I RNRs, which all of our studies are focused on and encompass the enzymes from all mammals, aerobically-growing Escherichia coli (Ec), and the human pathogen Chlamydia trachomatis (Ct), are comprised of two non-identical protein subunits, termed α and β. The α subunit contains the oxidizable C residue and the site of nucleotide reduction, whereas the β subunit assembles a metallocofactor cofactor, ~ 35 Å away from the site of catalysis in α. To reduce ribonucleotides, all RNRs must transfer an oxidizing equivalent or “hole”, stored at the metallocofactor in β, to α and generate the C• in a reversible process. The identity of metallocofactor is key distinguishing factor between the subclasses of class I RNRs, with the Ia and Ib enzymes utilizing diiron- and dimanganese-tyrosyl radical cofactors, and Ic employing a MnIV/FeIII cofactor. The first part of this thesis addresses the proper assembly of the MnIV/FeIII cofactor of Ct RNR. The heterodinuclear nature of the cofactor raises the question of which metal site, 1 or 2, houses the MnIV that functionally replaces the Y• of the class Ia enzyme’s cofactor. This work, a collaborative effort with the laboratory of Prof. Amy C. Rosenzweig at Northwestern University, answers this question using a combination of X-ray crystallography, spectroscopy, analytical metal-content analysis, and enzymatic activity assays. Our results, presented in Appendix A, established that in vitro, Mn is not inherently selective for a particular site, and that both 1Mn/2Fe and 1Fe/2Mn forms of the enzyme are assembled under different conditions. However, enzyme forms containing predominantly 1Mn/2Fe appear more active than those containing both 1Mn/2Fe and 1Fe/2Mn, and it is possible that 1Mn/2Fe is the only… Advisors/Committee Members: Joseph M Bollinger Jr., Dissertation Advisor/Co-Advisor, Carsten Krebs, Dissertation Advisor/Co-Advisor, Squire J Booker, Committee Member, Ming Tien, Committee Member, Christopher Howard House, Committee Member.

Subjects/Keywords: Ribonucleotide Reductase; metalloenzymes; dioxygen activation; Mössbauer; chlorite dismutase; electron paramagnetic resonance

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dassama, L. M. (2013). Mechanistic Investigations of Class I Ribonucleotide Reductases and Related Oxygen-utilizing Metalloenzymes. (Thesis). Penn State University. Retrieved from https://submit-etda.libraries.psu.edu/catalog/17413

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Dassama, Laura Massah. “Mechanistic Investigations of Class I Ribonucleotide Reductases and Related Oxygen-utilizing Metalloenzymes.” 2013. Thesis, Penn State University. Accessed March 08, 2021. https://submit-etda.libraries.psu.edu/catalog/17413.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Dassama, Laura Massah. “Mechanistic Investigations of Class I Ribonucleotide Reductases and Related Oxygen-utilizing Metalloenzymes.” 2013. Web. 08 Mar 2021.

Vancouver:

Dassama LM. Mechanistic Investigations of Class I Ribonucleotide Reductases and Related Oxygen-utilizing Metalloenzymes. [Internet] [Thesis]. Penn State University; 2013. [cited 2021 Mar 08]. Available from: https://submit-etda.libraries.psu.edu/catalog/17413.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Dassama LM. Mechanistic Investigations of Class I Ribonucleotide Reductases and Related Oxygen-utilizing Metalloenzymes. [Thesis]. Penn State University; 2013. Available from: https://submit-etda.libraries.psu.edu/catalog/17413

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Boston University

3. McNally, Joshua. Synthetic and density functional theory studies of dioxygen activating non-heme iron model complexes.

Degree: PhD, Chemistry, 2014, Boston University

URL: http://hdl.handle.net/2144/15130

► A long standing global scientific challenge has been the activation of O2 at a single metal center, and use of the subsequent metal-based oxidant for… (more)

▼ A long standing global scientific challenge has been the activation of O2 at a single metal center, and use of the subsequent metal-based oxidant for a variety of difficult chemical transformations. Towards this end, computational and synthetic methods have been utilized in an approach to develop model compounds capable of this type of chemistry, and to better understand the electronic and mechanistic properties of the observed catalytic reactivity. We have developed a first generation catalyst that has been shown to be fully functional in utilizing α-keto acids for the catalytic activation of O2 and oxidation of organic substrates in a highly conserved manner. This reactivity takes place at room temperature and standard pressure, and resembles the type of chemistry performed by mononuclear non-heme enzymes, which inspired the design of the catalyst. However, these solution-phase reactions do not benefit from the controlled environment provided by a protein active site, and solution studies and DFT simulations demonstrate an isomeric family of reactive species that ultimately deactivate via a dimerization pathway. A second generation catalyst, which incorporates ligand aromatic functionality, has been developed. This complex has been shown to catalytically oxide methanol to formaldehyde in the presence of α-ketoglutarate using O2. The aromatic group provides a synthetic platform, allowing a variety of substituents geared toward increasing complex solubility and the tuning of the redox properties of the metal center. Additionally, the ligand has been functionalized to allow for the immobilization of the catalyst using an azido-functionalized solid support, by means of 'click' chemistry. A procedure for the immobilization of the catalyst has been developed that sets the stage for the preparation of a material that will diminish dimerization and inactivation. Additional insights into potential reaction pathways of the first generation catalyst have been obtained from DFT studies. These simulations have provided energetic comparisons of proposed intermediates and set the stage for future computational and spectroscopic studies. This synergistic approach will not only allow for detailed electronic and mechanistic descriptions of the intimate mechanism, but will be used in the development of next generation catalysts that that can be tuned for desired reactivity properties.

Subjects/Keywords: Chemistry; Density functional theory; Dioxygen activation; Non-heme iron

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

McNally, J. (2014). Synthetic and density functional theory studies of dioxygen activating non-heme iron model complexes. (Doctoral Dissertation). Boston University. Retrieved from http://hdl.handle.net/2144/15130

Chicago Manual of Style (16^th Edition):

McNally, Joshua. “Synthetic and density functional theory studies of dioxygen activating non-heme iron model complexes.” 2014. Doctoral Dissertation, Boston University. Accessed March 08, 2021. http://hdl.handle.net/2144/15130.

MLA Handbook (7^th Edition):

McNally, Joshua. “Synthetic and density functional theory studies of dioxygen activating non-heme iron model complexes.” 2014. Web. 08 Mar 2021.

Vancouver:

McNally J. Synthetic and density functional theory studies of dioxygen activating non-heme iron model complexes. [Internet] [Doctoral dissertation]. Boston University; 2014. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2144/15130.

Council of Science Editors:

McNally J. Synthetic and density functional theory studies of dioxygen activating non-heme iron model complexes. [Doctoral Dissertation]. Boston University; 2014. Available from: http://hdl.handle.net/2144/15130

Boston University

4. Brazeau, Sarah Elizabeth. 3d metal complexes with the perfluoro-tert-butoxide and perfluoropinacolate ligands: dioxygen reduction and intermolecular substrate oxidation.

Degree: PhD, Chemistry, 2020, Boston University

URL: http://hdl.handle.net/2144/40354

► A CuI fully fluorinated O-donor monodentate alkoxide complex, K[Cu(OC4F9)2] (1), was previously shown to form a trinuclear copper–dioxygen species with a {Cu3(3-O)2} core, TOC4F9, upon… (more)

▼ A CuI fully fluorinated O-donor monodentate alkoxide complex, K[Cu(OC4F9)2] (1), was previously shown to form a trinuclear copper–dioxygen species with a {Cu3(3-O)2} core, TOC4F9, upon reactivity with O2 at low temperature. A significantly expanded kinetic and mechanistic study of TOC4F9 formation is reported using stopped-flow spectroscopy. The TOC4F9 complex performed catalytic oxidase conversion of para-hydroquinone (H2Q) to para-benzoquinone (BQ) and hydroxylation of 2,4-di-tert-butylphenolate (DBP) to catecholate, making TOC4F9 the first tri-copper species to perform tyrosinase (both monooxygenase and oxidase) chemistry. As opposed to 1, when K+ is fully encapsulated in {K(18C6)}[Cu(OC4F9)2] (4), O2 was not reduced under identical conditions. To study the effects of both alkali cation and the degree of encapsulation on reduction of O2, derivative complexes were synthesized with Na+ (16), {Na(DME)}+ (17), {Na(15C5)}+ (18), {K(15C5)}+ (19), {K(15C5)2}+ (20), Cs+ (21), {Cs(18C6)}+ (22), and {Cs(18C6)2}+ (23). Reduction of O2 was found to be encapsulation-dependent, and cation size was also determined to affect the chromophore observed. These results suggest that cation…F/O interactions between the CuI complexes assemble aggregates that are required to form reactive {Cun−O2} species. However, catalytic oxidation of H2Q to BQ and sub-stoichiometric oxidation of DBP to catecholate occurred regardless of whether a {Cun−O2} intermediate was detected, suggesting that a reactive species may self-assemble in the presence of substrate in all complex derivatives unable to reduce O2. A series of heteroleptic mixed phosphine/alkoxide 3d complexes was designed to evaluate PPh3 as a protecting group. Complexes of the form [(Ph3P)2M(OC4F9)2] (M= Fe (24), Co (25), Ni (26), Zn (27)) and [(Ph3P)2M(pinF)] (M= Co (31), Ni (32), Zn (33)) were prepared and characterized, along with related complexes with non-reactive L-donors for comparison, [(DME)Fe(OC4F9)2] (28) and [(Ph3PO)2M(OC4F9)2] (M= Fe (29), Ni (30)). Dimeric [Fe2(-O)(OPPh3)2(OC4F9)4] (36) was isolated after O2 reactivity with 24, and 28 and 29 were able to generate intermediate species capable of both oxidation of H2Q to BQ and oxygen atom transfer of thioanisole to methyl phenyl sulfoxide. The choice of fluorinated ligand influences O2 reactivity with CoII (25, 31), but not for NiII (26, 32). Related dimeric compounds [Co2(pinF)2(THF)4)] (34) and [Zn2(pinF)2(THF)2)] (35) were also isolated. Advisors/Committee Members: Doerrer, Linda H. (advisor), Whitty, Adrian (advisor).

Subjects/Keywords: Inorganic chemistry; C-H bond; Copper; Dioxygen; Fluorinated alkoxide; Oxidation; Phosphine

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Brazeau, S. E. (2020). 3d metal complexes with the perfluoro-tert-butoxide and perfluoropinacolate ligands: dioxygen reduction and intermolecular substrate oxidation. (Doctoral Dissertation). Boston University. Retrieved from http://hdl.handle.net/2144/40354

Chicago Manual of Style (16^th Edition):

Brazeau, Sarah Elizabeth. “3d metal complexes with the perfluoro-tert-butoxide and perfluoropinacolate ligands: dioxygen reduction and intermolecular substrate oxidation.” 2020. Doctoral Dissertation, Boston University. Accessed March 08, 2021. http://hdl.handle.net/2144/40354.

MLA Handbook (7^th Edition):

Brazeau, Sarah Elizabeth. “3d metal complexes with the perfluoro-tert-butoxide and perfluoropinacolate ligands: dioxygen reduction and intermolecular substrate oxidation.” 2020. Web. 08 Mar 2021.

Vancouver:

Brazeau SE. 3d metal complexes with the perfluoro-tert-butoxide and perfluoropinacolate ligands: dioxygen reduction and intermolecular substrate oxidation. [Internet] [Doctoral dissertation]. Boston University; 2020. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2144/40354.

Council of Science Editors:

Brazeau SE. 3d metal complexes with the perfluoro-tert-butoxide and perfluoropinacolate ligands: dioxygen reduction and intermolecular substrate oxidation. [Doctoral Dissertation]. Boston University; 2020. Available from: http://hdl.handle.net/2144/40354

University of Illinois – Urbana-Champaign

5. Letko, Christopher. Auxiliary proton-influenced metal-mediated reactions: dioxygen activation, anion coordination, and catalysis.

Degree: PhD, 0335, 2012, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/29511

► Studies on the incorporation of hydrogen-bonding groups into the second coordination sphere of Cu complexes have revealed that O2 reactivity is enhanced in the presence… (more)

▼ Studies on the incorporation of hydrogen-bonding groups into the second coordination sphere of Cu complexes have revealed that O2 reactivity is enhanced in the presence of these functional groups. The effects of intramolecular hydrogen-bonding on the oxygen affinity of CuN3+ derivatives, where N3 = tris(2-picolin-6-yl)methane (tripic) and analogues are presented in Chapter 2. The key synthetic methodology relies on Pd-catalyzed coupling reactions of lithiated 6-methyl-2-pyridone with bromopyridyl derivatives. These building blocks allow the preparation of tridentate N3 ligands decorated with OH and OMe substituents flanking the fourth coordination site of a tetrahedral complex. Crystallographic characterization of the ligand complemented with two methyl and one OH group revealed that it exists as the pyridone tautomer with a bifurcated hydrogen-bond. Coupling of these tridendate ligands gives the corresponding hydroxy- and methoxy-functionalized bis(tripodal) ligands. Cu[bis(2-methylpyrid-6-yl)(2-hydroxypyrid-6-yl)methane](NCMe)+ oxidizes readily in air to afford a mixed valence type III Cu1.5 dimer, and can be reversed through the addition of decamethylferrocene and acid. The reactivity with dioxygen requires the hydroxyl substituent: neither [Cu(tripic)(NCMe)]+ nor the methoxy complexes display O2 reactivity. A similar mixed valence dimer was found to form upon exposing the dicopper(I) complex of a tetrahydroxy bis(tridentate) ligand to air. The dicopper(I) complex of the analogous tetramethoxy N6-ligand instead reversibly binds O2. Deprotonation of Cu[bis(2-methylpyrid-6-yl)(2-hydroxypyrid-6-yl)methane](CO)+ afforded the neutral Cu(I) carbonyl complex. Deprotonation of Cu[bis(2-methylpyrid-6-yl)(2-hydroxypyrid-6-yl)methane](NCMe)+ gave a Cu(I) dimer that does not contain MeCN, which can be reoxidized, reprotonated, and carbonylated. The structures of bis(2-methylpyrid-6-yl)(2-pyridon-6-yl)methane, a bimetallic Cu(I)(NCMe) complex of the N6-tetramethoxylated ligand, and two mixed valence Cu dimers were confirmed by single crystal X-ray diffraction. Electrochemical O2 reduction studies of these Cu complexes were undertaken, in addition to various Cu complexes reported in literature. The oxygen reduction reaction (ORR) onset potential of Cu[bis(2-methylpyrid-6-yl)(2-hydroxypyrid-6-yl)methane](NCMe)+ (0.46 V) was found to be more positive than its methoxylated derivative (0.29 V), in addition to hemocyanin model complexes [Cu(tripic)(NCMe)]+ (0.34 V) and its tethered bimetallic derivative, [Cu2(bistripic)(NCMe)2]2+ (0.40 V) (all potentials vs RHE at pH = 2). [Cu(tpa)](ClO4)2 (tpa = tris(2-pyridylmethyl)amine) was found to have the highest reported onset potential for the ORR (0.53 V) for a Cu complex at low pH. The ORR activity of Cu(II)(ClO4)2 salts ligated to tpa derivatives were studied, including a new tpa ligand functionalized with a ferrocenyl group (tpa-Fc). All derivatives were shown to display similar or lower catalytic activity relative to the parent complex [Cu(tpa)](ClO4)2. A… Advisors/Committee Members: Rauchfuss, Thomas B. (advisor), Gewirth, Andrew A. (committee member), Katzenellenbogen, John A. (committee member), Shapley, Patricia A. (committee member).

Subjects/Keywords: Dioxygen Reduction; Second Coordination Sphere; Hydrogen Bonding; Transfer Hydrogenation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Letko, C. (2012). Auxiliary proton-influenced metal-mediated reactions: dioxygen activation, anion coordination, and catalysis. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/29511

Chicago Manual of Style (16^th Edition):

Letko, Christopher. “Auxiliary proton-influenced metal-mediated reactions: dioxygen activation, anion coordination, and catalysis.” 2012. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed March 08, 2021. http://hdl.handle.net/2142/29511.

MLA Handbook (7^th Edition):

Letko, Christopher. “Auxiliary proton-influenced metal-mediated reactions: dioxygen activation, anion coordination, and catalysis.” 2012. Web. 08 Mar 2021.

Vancouver:

Letko C. Auxiliary proton-influenced metal-mediated reactions: dioxygen activation, anion coordination, and catalysis. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2012. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2142/29511.

Council of Science Editors:

Letko C. Auxiliary proton-influenced metal-mediated reactions: dioxygen activation, anion coordination, and catalysis. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2012. Available from: http://hdl.handle.net/2142/29511

University of Maryland

6. Pal, Shrinwantu. Mechanistic investigations of stoichiometric and catalytic Pt-mediated oxidative functionalization at a proximal boron center.

Degree: Chemistry, 2013, University of Maryland

URL: http://hdl.handle.net/1903/14897

► The focus of the work detailed in this dissertation is the investigation of mechanism and catalytic applications of Pt complexes supported by novel anionic di(2-pyridyl)borate… (more)

▼ The focus of the work detailed in this dissertation is the investigation of mechanism and catalytic applications of Pt complexes supported by novel anionic di(2-pyridyl)borate ligands. It was found that oxidation of Me,MeBPy2-supported PtII complexes bearing no hydrocarbyl complexes directly generated dimethyl ether in quantitative yields, with one methyl originating from the MeB fragment. We also found that increasing formal charge on the metal center renders related complexes reluctant to undergo oxidation. Based on a proposed mechanism involving a transient PtIV-Me complex, we set out to develop a series of modified R,RBPy2 ligands to prevent such oxidatively induced hydrocarbyl transfer. We found that the strategy of replacing one hydrocarbyl (Me) group in the dmdpb ligand by methoxo (OMe) was not sufficient in completely preventing degradation of the borate center. However, derived mono- and di-hydrocarbyl PtII complexes could still be easily oxidized under aerobic conditions. Interestingly, oxidation products corresponding to both B-to-PtIV methyl migration and ligand retention were observed. We focused our attention to a unique 1,5-cyclooctanediylBPy2 ligand, which, we presumed, would prevent hydrocarbyl migration due to the rigid structure imposed by the bicyclic framework. The derived PtIVMe3 complex was found to exhibit `enhanced' BC-H agostic stabilization of the penta-coordinate PtIV center. Oxidation of derived PtII complexes results in hydride migration from the B-CH fragment onto the PtIV center, led to the formation of a series of (MeO),(MeO)BPy2 supported Pt complexes, and unanticipated C-C and C=C coupling at the borate center. The (MeO),(MeO)BPy2 ligand proved to be the first example of anionic facially chelating borate ligand capable of resisting oxidative degradation. The derived PtIV(Ph)2(OH) can be used for catalytic aerobic oxidation of NaBH(OMe)3 and NaBH4, with TOFs of 178/h and 216/h respectively. This may be of particular interest from the perspective of a direct-borohydride-fuel-cell (DBFC). We also found that the PtIV(Ph)2(OH) complex could be used as a catalyst to oxidize isopropanol to acetone under aerobic conditions with a TON of 3.8 after 56h at 80 °C. A mechanism involving selective hydride migration from a B-bound isopropoxy fragment to the PtIV center was proposed. Advisors/Committee Members: Vedernikov, Andrei N (advisor).

Subjects/Keywords: Chemistry; Inorganic chemistry; Organic chemistry; aerobic; Borate; catalysis; dioxygen; homogeneous; Platinum

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Pal, S. (2013). Mechanistic investigations of stoichiometric and catalytic Pt-mediated oxidative functionalization at a proximal boron center. (Thesis). University of Maryland. Retrieved from http://hdl.handle.net/1903/14897

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Pal, Shrinwantu. “Mechanistic investigations of stoichiometric and catalytic Pt-mediated oxidative functionalization at a proximal boron center.” 2013. Thesis, University of Maryland. Accessed March 08, 2021. http://hdl.handle.net/1903/14897.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Pal, Shrinwantu. “Mechanistic investigations of stoichiometric and catalytic Pt-mediated oxidative functionalization at a proximal boron center.” 2013. Web. 08 Mar 2021.

Vancouver:

Pal S. Mechanistic investigations of stoichiometric and catalytic Pt-mediated oxidative functionalization at a proximal boron center. [Internet] [Thesis]. University of Maryland; 2013. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1903/14897.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Pal S. Mechanistic investigations of stoichiometric and catalytic Pt-mediated oxidative functionalization at a proximal boron center. [Thesis]. University of Maryland; 2013. Available from: http://hdl.handle.net/1903/14897

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

7. Schneider, Ludovic. Systèmes hybrides photosensibilisateur-laccase pour la catalyse d'oxydation de composés organiques : Hybrid photosensitizer-laccase systems for the oxidation of organic compounds.

Degree: Docteur es, Sciences chimiques, 2014, Aix Marseille Université

URL: http://www.theses.fr/2014AIXM4372

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Les laccases sont des enzymes de type oxydase, réalisant de manière efficace la réduction du dioxygène en eau. Des études réalisées au laboratoire ont permis… (more)

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Les laccases sont des enzymes de type oxydase, réalisant de manière efficace la réduction du dioxygène en eau. Des études réalisées au laboratoire ont permis de montrer que l’irradiation sous atmosphère inerte d’un système de type, EDTA/[Ru(bpy)3]2+/laccase, conduisait à la photoréduction de l’enzyme via la formation d'une espèce [Ru(bpy)3]2+*. La substitution de l’EDTA par un alcène de type p-styrène sulfonate conduit également à la photoréduction de l’enzyme. L'ouverture à l'air du système permet une consommation d’oxygène concomitante à la détection par RMN de produits d’oxydation tels que l’époxyde, le diol et le p-benzaldéhyde sulfonate. L’influence de la concentration des différents partenaires, de la source d’irradiation et du pH sur l’efficacité de cette réaction a été évaluée. D’autres alcènes tels que le styrène, le cyclohéxène ou le cyclooctène sont également substrats. Le marquage isotopique en présence soit d'H218O soit d'18O2 ainsi que l’utilisation de générateurs d’espèces réactives de l’oxygène, ont permis de proposer un mécanisme majoritaire où l’espèce RuIII, photoproduite avec l'assistance de la laccase, pourrait arracher un électron du substrat qui à son tour réagirait avec le dioxygène présent dans le milieu pour conduire aux produits observés. D’autres complexes photoactivables à base de ruthénium ou de manganèse ont également été employés. Afin d’aborder le contrôle de la réactivité, le greffage covalent d’un photosensibilisateur à base de ruthénium sur une lysine unique à proximité du site d'oxydation des substrats de l'enzyme a été effectué.

Laccases are oxidases that efficiently perform the reduction of dioxygen into water. Studies in the laboratory have allowed to show that irradiation under inert atmosphere of a EDTA/[Ru(bpy)3]2+/laccase system, lead to the photoreduction of the enzyme via the irradiation of [Ru(bpy)3]2+*. The substitution of EDTA by the alkene p-styrene sulfonate results similarly in a photoreduction of the enzyme. Opening the system to air allows a dioxygen consumption with a simultaneous detection of oxidation products such as the epoxide, diol and p-benzaldehyde sulfonate detected by NMR. The influence of the concentration of the partners, the irradiation source and pH on the efficiency of the reaction was evaluated. Other alkenes such as styrene, cyclohexene and cyclooctene are also substrates. Isotopic labeling experiments in the presence of either H218O or 18O2, as well as the use of reactive oxygen species generators, allowed us to propose a main mechanism where the laccase assisted RuIII photogenerated specie would withdraw an electron from the substrate which in turn would react with dioxygen to yield the products observed. Other ruthenium and manganese photosensitizers were also used. To address the control of the reactivity, a covalent grafting of a ruthenium photosensitizer, on a unique lysine nearby the substrate oxidation site of the laccase was done.

Advisors/Committee Members: Tron, Thierry (thesis director), Mekmouche, Yasmina (thesis director).

Subjects/Keywords: Oxygénation; Dioxygène; Styrène; Alcènes; Ruthénium; Laccase; Oxygenation; Dioxygen; Styrene; Alkenes; Ruthenium; Laccase

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Schneider, L. (2014). Systèmes hybrides photosensibilisateur-laccase pour la catalyse d'oxydation de composés organiques : Hybrid photosensitizer-laccase systems for the oxidation of organic compounds. (Doctoral Dissertation). Aix Marseille Université. Retrieved from http://www.theses.fr/2014AIXM4372

Chicago Manual of Style (16^th Edition):

Schneider, Ludovic. “Systèmes hybrides photosensibilisateur-laccase pour la catalyse d'oxydation de composés organiques : Hybrid photosensitizer-laccase systems for the oxidation of organic compounds.” 2014. Doctoral Dissertation, Aix Marseille Université. Accessed March 08, 2021. http://www.theses.fr/2014AIXM4372.

MLA Handbook (7^th Edition):

Schneider, Ludovic. “Systèmes hybrides photosensibilisateur-laccase pour la catalyse d'oxydation de composés organiques : Hybrid photosensitizer-laccase systems for the oxidation of organic compounds.” 2014. Web. 08 Mar 2021.

Vancouver:

Schneider L. Systèmes hybrides photosensibilisateur-laccase pour la catalyse d'oxydation de composés organiques : Hybrid photosensitizer-laccase systems for the oxidation of organic compounds. [Internet] [Doctoral dissertation]. Aix Marseille Université 2014. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2014AIXM4372.

Council of Science Editors:

Schneider L. Systèmes hybrides photosensibilisateur-laccase pour la catalyse d'oxydation de composés organiques : Hybrid photosensitizer-laccase systems for the oxidation of organic compounds. [Doctoral Dissertation]. Aix Marseille Université 2014. Available from: http://www.theses.fr/2014AIXM4372

University of California – Irvine

8. Cook, Sarah. Principles of Molecular Design in the Development of Ligand Frameworks that Control the Primary and Secondary Coordination Spheres of Metal Ions.

Degree: Chemistry, 2015, University of California – Irvine

URL: http://www.escholarship.org/uc/item/9bv209vn

► Metalloproteins have evolved to contain specific combinations of primary and secondary coordination spheres within their active sites that contribute to the high activity and selectivity… (more)

▼ Metalloproteins have evolved to contain specific combinations of primary and secondary coordination spheres within their active sites that contribute to the high activity and selectivity of their chemical transformations. One approach to developing small molecule analogs with comparable reactivity is to design molecular constructs that exhibit similar control over aspects of the primary and secondary coordination spheres. This dissertation describes the design and reactivity of multifunctional ligands that position hydrogen-bond acceptors within the secondary coordination spheres of transition metal complexes. Two classes of ligands were studied: the first is a tetradentate, tripodal ligand ([MST]3-) that was previously demonstrated to support formation of heterobimetallic complexes containing a Mn center and a redox inactive metal ion. The extension to the Fe analog is described here, as well as the continued examination of the influence of group 2 metal ions on the properties and reactivity of both the Mn and Fe complexes. The most important finding of these studies is that Ca(II) and Sr(II) ions impart nearly identical influences on the Mn and Fe centers—a result with relevance to biological water oxidation. Reaction of [MnMST]– and [FeMST]– with oxygen-atom transfer reagents in the absence of secondary metal ions uncovered a limitation of the [MST]3- ligand system in which weak C–H bonds are susceptible to intramolecular oxidation. In order to address this limitation, ligand derivatives were designed that removed weak C–H bonds, which led to the observation of a putative Fe(IV)–oxo intermediate. The last two chapters of this dissertation describe the development of a new type of ligand that utilizes a tridentate, redox-active framework that has been shown to provide access to multi-electron transformations at first row transition metal centers. The first derivative of this ligand was shown to form dinuclear complexes of Fe, Co, and Cu with a pre-organized binding pocket for secondary metal ions. Modification of the steric bulk of the ligand prevented formation of these dinuclear complexes and instead supported mononuclear Fe and Co centers. The structural, electronic, and electrochemical properties of both of these series of complexes are described.

Subjects/Keywords: Chemistry; Inorganic chemistry; Dioxygen activation; Heterobimetallic clusters; Hydrogen-bonding; Molecular Design; Redox active ligands; Secondary coordination sphere

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Cook, S. (2015). Principles of Molecular Design in the Development of Ligand Frameworks that Control the Primary and Secondary Coordination Spheres of Metal Ions. (Thesis). University of California – Irvine. Retrieved from http://www.escholarship.org/uc/item/9bv209vn

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Cook, Sarah. “Principles of Molecular Design in the Development of Ligand Frameworks that Control the Primary and Secondary Coordination Spheres of Metal Ions.” 2015. Thesis, University of California – Irvine. Accessed March 08, 2021. http://www.escholarship.org/uc/item/9bv209vn.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Cook, Sarah. “Principles of Molecular Design in the Development of Ligand Frameworks that Control the Primary and Secondary Coordination Spheres of Metal Ions.” 2015. Web. 08 Mar 2021.

Vancouver:

Cook S. Principles of Molecular Design in the Development of Ligand Frameworks that Control the Primary and Secondary Coordination Spheres of Metal Ions. [Internet] [Thesis]. University of California – Irvine; 2015. [cited 2021 Mar 08]. Available from: http://www.escholarship.org/uc/item/9bv209vn.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Cook S. Principles of Molecular Design in the Development of Ligand Frameworks that Control the Primary and Secondary Coordination Spheres of Metal Ions. [Thesis]. University of California – Irvine; 2015. Available from: http://www.escholarship.org/uc/item/9bv209vn

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université Paris-Sud – Paris XI

9. Ségaud, Nathalie. Étude de l’activation réductrice du dioxygène par un complexe de fer (II) et nouveaux complexes hétérodinucléaires : contributions pour le développement de catalyseurs d’oxydation bioinspirés : Study of dioxygen activation by an iron(II) complex and new heterodinuclear complexes : contributions for the development of bioinspired oxydation catalysts.

Degree: Docteur es, Chimie inorganique, 2013, Université Paris-Sud – Paris XI

URL: http://www.theses.fr/2013PA112329

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Les enjeux économiques et écologiques actuels requièrent le développement de réactions et procédés respectueux de l'environnement. Dans ce cadre, nous étudions l'oxydation des hydrocarbures dans… (more)

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Les enjeux économiques et écologiques actuels requièrent le développement de réactions et procédés respectueux de l'environnement. Dans ce cadre, nous étudions l'oxydation des hydrocarbures dans des conditions douces, un problème que la Nature a résolu en mettant en œuvre des enzymes dont le site actif contient un ou deux ions du fer, pour obtenir des produits avec efficacité et sélectivité. Parmi ces systèmes, les MonoOxygénases (MO) catalysent l'insertion d'un atome d'oxygène dans une liaison chimique d'un substrat organique inerte (S). Cela passe par l'activation réductrice du dioxygène ce qui mène à des intermédiaires très oxydants de type FeIII-(hydro)peroxo et Fe-Oxo (i.e. FeIV=O ou FeV=O).En utilisant des complexes très simples, nous avons préparé et identifié des intermédiaires réactionnels FeIII-peroxo et FeIV-oxo, à l'aide d'oxydants chimiques (H2O2, peroxydes, peracides...) ou de O2 et d'un réducteur, selon une réaction analogue aux MO à un atome de fer. Ces intermédiaires se sont montrés efficaces, respectivement pour l'hydroxylation catalytique des aromatiques et pour l'oxydation des oléfines et des alcanes, mais souffrent souvent d'un manque de sélectivité. De plus, les intermédiaires générés en présence d’O2 sont consommés par réaction indésirable avec le réducteur chimique ou son sous-produit d’oxydation, rendant la catalyse d’oxydation non réalisable dans ces conditions. Différentes stratégies ont été adoptées lors de cette thèse afin de mimer au mieux l’activité des enzymes et reproduire l’efficacité et la sélectivité de ces réactions d’oxydations.Ainsi, une cavité artificielle (calix[6]arène) a été greffée à nos complexes de fer. Une étude du site catalytique portant une fonction triazole résultant de la chimie « click » a été réalisée. La synthèse d’un nouveau complexe fer-zinc a ensuite été réalisée, où l’insertion des métaux dans leur site de coordination destiné est maîtrisée. L’insertion d’un substrat à l’intérieur de la cavité calixarène a été réalisée, permettant d’obtenir un système qui pourrait améliorer la sélectivité et l’efficacité des réactions d’oxydations des alcanes.La seconde stratégie développée a été d’utiliser une électrode comme source d’électrons lors de l’activation du dioxygène par un complexe de fer(II). L’étude par voltampérométrie cyclique de cette réaction a permis de démontrer la formation d’un adduit FeII-O2 en conditions réductrices. Un intermédiaire FeIII-peroxo a par la suite été détecté en oxydation, qui génère une espèce à haut degré d’oxydation. Cet intermédiaire généré directement en solution à l’aide d’H2O2 pourrait alors réaliser les réactions d’oxydations en conditions oxydantes. De nouveaux systèmes électrocatalytiques pourraient alors être développés.

MonoOxygenases (MO) such as cytochromes P450 catalyse the oxygen atom insertion into a chemical bond of an inert organic substrate following reductive activation of dioxygen. By using very simple Fe(II) complexes bearing amine/pyridine ligands, it is possible to prepare reactive species such as Fe(III)OOH…

Advisors/Committee Members: Banse, Frédéric (thesis director).

Subjects/Keywords: Chimie bioinspirée; Activation du dioxygène; Réaction d’oxydation; Chimie de coordination; Bioinspired chemistry; Dioxygen activation; Oxidation reactions; Coordination chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Ségaud, N. (2013). Étude de l’activation réductrice du dioxygène par un complexe de fer (II) et nouveaux complexes hétérodinucléaires : contributions pour le développement de catalyseurs d’oxydation bioinspirés : Study of dioxygen activation by an iron(II) complex and new heterodinuclear complexes : contributions for the development of bioinspired oxydation catalysts. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2013PA112329

Chicago Manual of Style (16^th Edition):

Ségaud, Nathalie. “Étude de l’activation réductrice du dioxygène par un complexe de fer (II) et nouveaux complexes hétérodinucléaires : contributions pour le développement de catalyseurs d’oxydation bioinspirés : Study of dioxygen activation by an iron(II) complex and new heterodinuclear complexes : contributions for the development of bioinspired oxydation catalysts.” 2013. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed March 08, 2021. http://www.theses.fr/2013PA112329.

MLA Handbook (7^th Edition):

Ségaud, Nathalie. “Étude de l’activation réductrice du dioxygène par un complexe de fer (II) et nouveaux complexes hétérodinucléaires : contributions pour le développement de catalyseurs d’oxydation bioinspirés : Study of dioxygen activation by an iron(II) complex and new heterodinuclear complexes : contributions for the development of bioinspired oxydation catalysts.” 2013. Web. 08 Mar 2021.

Vancouver:

Ségaud N. Étude de l’activation réductrice du dioxygène par un complexe de fer (II) et nouveaux complexes hétérodinucléaires : contributions pour le développement de catalyseurs d’oxydation bioinspirés : Study of dioxygen activation by an iron(II) complex and new heterodinuclear complexes : contributions for the development of bioinspired oxydation catalysts. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2013. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2013PA112329.

Council of Science Editors:

Ségaud N. Étude de l’activation réductrice du dioxygène par un complexe de fer (II) et nouveaux complexes hétérodinucléaires : contributions pour le développement de catalyseurs d’oxydation bioinspirés : Study of dioxygen activation by an iron(II) complex and new heterodinuclear complexes : contributions for the development of bioinspired oxydation catalysts. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2013. Available from: http://www.theses.fr/2013PA112329

10. Mangue, Jordan. Synthèse de complexes de cuivre bio-inspirés pour la réduction catalytique de l'oxyde nitreux et du dioxygène : Bio-inspired copper complexes syntheses for catalytic nitrous oxide and dioxygen reduction.

Degree: Docteur es, Chimie inorganique et bio inorganique, 2018, Université Grenoble Alpes (ComUE)

URL: http://www.theses.fr/2018GREAV050

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N2O est le troisième plus important gaz à effet de serre ainsi qu’un des principaux gaz responsables de la dégradation de la couche d’ozone. Une… (more)

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N2O est le troisième plus important gaz à effet de serre ainsi qu’un des principaux gaz responsables de la dégradation de la couche d’ozone. Une approche bio-inspirée de la N2Oréductase (N2Or), enzyme réduisant N2O via un site actif comportant quatre ions cuivre pontés par un atome de soufre, aide au design de nouveaux systèmes. Six complexes à valences mixtes comportant un motif Cu2(µ-S) considéré comme minimum pour avoir une activité ont alors été synthétisés. Il a été démontré que la structure de ces centres métalliques est affectée par le solvant utilisé. Dans un solvant non coordinant comme l’acétone, tous les complexes possèdent une liaison intermétallique et une valence délocalisée à température ambiante. En revanche en solvant coordinant, la coordination de molécules d’acétonitrile rend impossible la formation de liaison intermétallique et localise la valence.Pour tester l’activité N2Or de ces complexes, un prototype permettant un bullage constant en cuve UV a été conçu. L’objectif est de mettre au point une réduction catalytique de N2O en utilisant un réducteur sacrificiel et une source de proton. Le gaz utilisé lors des tests semble cependant contenir une faible quantité de O2 empêchant la caractérisation des activités. Une optimisation visant à purifier N2O avant les tests est en cours.Par ailleurs, les réductions de O2 à deux électrons pour former H2O2 (un oxydant doux) et à quatre électrons pour former H2O (réaction utilisée dans les piles à combustibles) en font un domaine attractif. Il a été démontré que tous les complexes synthétisés lors de ces travaux sont capables de réduire catalytiquement O2 dans l’acétone et que seulement celui sans position échangeable est actif dans l’acétonitrile. Ce dernier a de plus montré une capacité à changer de sélectivité (H2O2 vs H2O) en fonction de la concentration en réducteur sacrificiel utilisé.

N2O is the third most important global warming gas and one of the most aggressive gas against ozone layer. A bio-inspired approach from N2Oreductase (N2Or), enzyme catalysing the two electron reduction of N2O with a four sulfur-bridged copper ions centre, helps for the design of new systems. Six mixed valent copper complexes containing the minimum Cu2(µ-S) core were then synthetized. It has been shown that these structures are affected by solvents in solution. Indeed, in a non-coordinating solvent like acetone, all these complexes have an intermetallic bond and a delocalized valence at room temperature. However in a coordinating solvent, the acetonitrile coordination makes it impossible to form a Cu-Cu bond and localize the valences.To test the N2Or activity, a prototype allowing a constant N2O bubbling in a UV cuve using a closed system was designed. The aim is to develop a catalytic reduction using sacrificial reductant and proton source. However, the gas bottle used for activity tests seems to contain a small amounts of O2 preventing results interpretation. The aim is now to optimize the prototype by adding a system that can purify N2O before activity tests.In a…

Advisors/Committee Members: Torelli, Stéphane (thesis director), Ménage, Stéphane (thesis director).

Subjects/Keywords: Chimie bio-Inorganique; Bio-Inspiration; Catalyse; Dioxygène; Oxyde nitreux; Cuivre; Bio-Inorganic chemistry; Bio-Inspiration; Catalysis; Dioxygen; Nitrous oxyde; Copper; 540

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mangue, J. (2018). Synthèse de complexes de cuivre bio-inspirés pour la réduction catalytique de l'oxyde nitreux et du dioxygène : Bio-inspired copper complexes syntheses for catalytic nitrous oxide and dioxygen reduction. (Doctoral Dissertation). Université Grenoble Alpes (ComUE). Retrieved from http://www.theses.fr/2018GREAV050

Chicago Manual of Style (16^th Edition):

Mangue, Jordan. “Synthèse de complexes de cuivre bio-inspirés pour la réduction catalytique de l'oxyde nitreux et du dioxygène : Bio-inspired copper complexes syntheses for catalytic nitrous oxide and dioxygen reduction.” 2018. Doctoral Dissertation, Université Grenoble Alpes (ComUE). Accessed March 08, 2021. http://www.theses.fr/2018GREAV050.

MLA Handbook (7^th Edition):

Mangue, Jordan. “Synthèse de complexes de cuivre bio-inspirés pour la réduction catalytique de l'oxyde nitreux et du dioxygène : Bio-inspired copper complexes syntheses for catalytic nitrous oxide and dioxygen reduction.” 2018. Web. 08 Mar 2021.

Vancouver:

Mangue J. Synthèse de complexes de cuivre bio-inspirés pour la réduction catalytique de l'oxyde nitreux et du dioxygène : Bio-inspired copper complexes syntheses for catalytic nitrous oxide and dioxygen reduction. [Internet] [Doctoral dissertation]. Université Grenoble Alpes (ComUE); 2018. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2018GREAV050.

Council of Science Editors:

Mangue J. Synthèse de complexes de cuivre bio-inspirés pour la réduction catalytique de l'oxyde nitreux et du dioxygène : Bio-inspired copper complexes syntheses for catalytic nitrous oxide and dioxygen reduction. [Doctoral Dissertation]. Université Grenoble Alpes (ComUE); 2018. Available from: http://www.theses.fr/2018GREAV050

University of Florida

11. Di Francesco, Gianna N. A Series of Tricopper Macrobicyclic Complexes: Reactivity and Tunability via Simple Modifications.

Degree: PhD, Chemistry, 2015, University of Florida

URL: https://ufdc.ufl.edu/UFE0049065

Subjects/Keywords: chemistry; copper; dioxygen; n2o; organometallics; reactivity; sulfur

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Di Francesco, G. N. (2015). A Series of Tricopper Macrobicyclic Complexes: Reactivity and Tunability via Simple Modifications. (Doctoral Dissertation). University of Florida. Retrieved from https://ufdc.ufl.edu/UFE0049065

Chicago Manual of Style (16^th Edition):

Di Francesco, Gianna N. “A Series of Tricopper Macrobicyclic Complexes: Reactivity and Tunability via Simple Modifications.” 2015. Doctoral Dissertation, University of Florida. Accessed March 08, 2021. https://ufdc.ufl.edu/UFE0049065.

MLA Handbook (7^th Edition):

Di Francesco, Gianna N. “A Series of Tricopper Macrobicyclic Complexes: Reactivity and Tunability via Simple Modifications.” 2015. Web. 08 Mar 2021.

Vancouver:

Di Francesco GN. A Series of Tricopper Macrobicyclic Complexes: Reactivity and Tunability via Simple Modifications. [Internet] [Doctoral dissertation]. University of Florida; 2015. [cited 2021 Mar 08]. Available from: https://ufdc.ufl.edu/UFE0049065.

Council of Science Editors:

Di Francesco GN. A Series of Tricopper Macrobicyclic Complexes: Reactivity and Tunability via Simple Modifications. [Doctoral Dissertation]. University of Florida; 2015. Available from: https://ufdc.ufl.edu/UFE0049065

12. Bohn, Antoine. Approche électrochimique de l'activation réductrice du dioxygène à l'aide d'un complexe de fer(II) non hémique : Electrochemical Approach of the Reductive Activation of O2 by a Non heme Fe(II) complex.

Degree: Docteur es, Chimie, 2018, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2018SACLS471

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Les cytochromes P450 sont des enzymes mononucléaires de fer qui catalysent l’oxydation de liaisons C-H en utilisant le dioxygène de l’air. L’activation de O2 nécessite… (more)

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Les cytochromes P450 sont des enzymes mononucléaires de fer qui catalysent l’oxydation de liaisons C-H en utilisant le dioxygène de l’air. L’activation de O2 nécessite sa réduction partielle par l'apport de deux protons et deux électrons. Ces derniers sont fournis par le réducteur naturel NADPH par l'intermédiaire d'une flavoprotéine qui permet de convertir l’adduit fer(II)-O2 en un intermédiaire de type fer(III)-peroxo dont les protonations successives permettent la rupture hétérolytique de la liaison O—O et l’obtention d’un intermédiaire de type fer-oxo responsable de l’oxydation du substrat.1 Ce projet s’inscrit dans le cadre de la chimie bio-inspirée, il a pour objectif de développer des catalyseurs de fer non-hémiques afin de réaliser l’oxydation de petites molécules organiques en utilisant le dioxygène de l’air. L’activation du dioxygène est assurée par le biais d’une électrode qui sert de source d’électrons mais également de sonde mécanistique. Pour comprendre le mécanisme de l’activation du dioxygène il est nécessaire (i) de générer les intermédiaires réactionnels oxydants (fer-oxo, fer-(hydro)peroxo) par le biais d’oxydants chimiques comme le PhIO et H2O2 puis (ii) de les caractériser par spectroscopie et électrochimie à basse température. Enfin (iii) l’étude expérimentale par voltampérométrie cyclique de la réaction du complexe de Fe(II) en présence de dioxygène couplée à des simulations de voltampérogrammes de cette même réaction (à l’aide de données thermodynamiques et cinétiques obtenues en (ii)) permettent ainsi de valider le mécanisme de l’activation réductrice du dioxygène de ce système. Ce travail a démontré que les complexes de FeII avec des ligands amines/pyridine peuvent activer le dioxygène à la surface d’une électrode en suivant un mécanisme proche de celui du cytochrome P450. A présent, la difficulté principale est de s’affranchir de la réduction prématurée des intermédiaires lorsqu’ils sont générés à l’électrode. En se basant sur ces résultats, l’essentiel du travail est à présent ciblé sur la compréhension des différents paramètres (première sphère de coordination, conditions expérimentales, …) qui peuvent modifier la stabilité des intermédiaires et donc l’efficacité de la catalyse.

Cytochrome P450 is a mononuclear iron enzyme, which catalyzes the oxidation of robust C-H bonds using O2. Activation of O2 is achieved at the Fe(II) center and requires an electron transfer to convert the iron(II)-dioxygen adduct into an iron(III)peroxo intermediate. After protonation, this latter may directly oxidize substrates or evolves to yield a powerful high valent iron-oxo moiety. In such natural systems, the necessary electrons are provided by a co-substrate NAD(P)H and are conveyed through a reductase.1The aim of this project is to develop non-heme iron(II) complexes as catalysts for the oxidation of small organic molecules by O2. Our objective is to use an electrode to deliver the electrons while providing mechanistic information at the same time thanks to a combined experimental/simulation approach…

Advisors/Committee Members: Banse, Frédéric (thesis director).

Subjects/Keywords: Chimie bio-inspirée; Voltampérométrie cyclique.; Activation réductrice du dioxygène; Bioinspired chemistry; Cyclic voltammetry; Reductive activation of dioxygen

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Bohn, A. (2018). Approche électrochimique de l'activation réductrice du dioxygène à l'aide d'un complexe de fer(II) non hémique : Electrochemical Approach of the Reductive Activation of O2 by a Non heme Fe(II) complex. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2018SACLS471

Chicago Manual of Style (16^th Edition):

Bohn, Antoine. “Approche électrochimique de l'activation réductrice du dioxygène à l'aide d'un complexe de fer(II) non hémique : Electrochemical Approach of the Reductive Activation of O2 by a Non heme Fe(II) complex.” 2018. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed March 08, 2021. http://www.theses.fr/2018SACLS471.

MLA Handbook (7^th Edition):

Bohn, Antoine. “Approche électrochimique de l'activation réductrice du dioxygène à l'aide d'un complexe de fer(II) non hémique : Electrochemical Approach of the Reductive Activation of O2 by a Non heme Fe(II) complex.” 2018. Web. 08 Mar 2021.

Vancouver:

Bohn A. Approche électrochimique de l'activation réductrice du dioxygène à l'aide d'un complexe de fer(II) non hémique : Electrochemical Approach of the Reductive Activation of O2 by a Non heme Fe(II) complex. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2018. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2018SACLS471.

Council of Science Editors:

Bohn A. Approche électrochimique de l'activation réductrice du dioxygène à l'aide d'un complexe de fer(II) non hémique : Electrochemical Approach of the Reductive Activation of O2 by a Non heme Fe(II) complex. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2018. Available from: http://www.theses.fr/2018SACLS471

University of Minnesota

13. Hong, Sungjun. Reactions of copper complexes with dioxygen and oxo transfer reagents: toward elusive copper-oxyl species.

Degree: PhD, Chemistry, 2010, University of Minnesota

URL: http://purl.umn.edu/94402

► The binding and activation of dioxygen by Cu ions is central to the function of numerous biological systems. Among the enzymes activate dioxygen for the… (more)

Subjects/Keywords: Activation; Copper; Copper-oxyl; Dioxygen; Enzyme; Synthetic model; Chemistry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Hong, S. (2010). Reactions of copper complexes with dioxygen and oxo transfer reagents: toward elusive copper-oxyl species. (Doctoral Dissertation). University of Minnesota. Retrieved from http://purl.umn.edu/94402

Chicago Manual of Style (16^th Edition):

Hong, Sungjun. “Reactions of copper complexes with dioxygen and oxo transfer reagents: toward elusive copper-oxyl species.” 2010. Doctoral Dissertation, University of Minnesota. Accessed March 08, 2021. http://purl.umn.edu/94402.

MLA Handbook (7^th Edition):

Hong, Sungjun. “Reactions of copper complexes with dioxygen and oxo transfer reagents: toward elusive copper-oxyl species.” 2010. Web. 08 Mar 2021.

Vancouver:

Hong S. Reactions of copper complexes with dioxygen and oxo transfer reagents: toward elusive copper-oxyl species. [Internet] [Doctoral dissertation]. University of Minnesota; 2010. [cited 2021 Mar 08]. Available from: http://purl.umn.edu/94402.

Council of Science Editors:

Hong S. Reactions of copper complexes with dioxygen and oxo transfer reagents: toward elusive copper-oxyl species. [Doctoral Dissertation]. University of Minnesota; 2010. Available from: http://purl.umn.edu/94402

University of Georgia

14. Emerson, Joseph Patrick. The kinetics and mechanism of superoxide reduction by two-iron superoxide reductase from Desulfovibrio vulgaris.

Degree: 2014, University of Georgia

URL: http://hdl.handle.net/10724/20776

► Superoxide reductase (SOR) has been recently found in anaerobic bacteria and archaea, and is proposed to be involved in a pathway of oxidative resistance. The… (more)

Subjects/Keywords: Superoxide reductase; Desulfovibrio vulgaris; Oxidative stress; Oxidative stress resistance; Pulse radiolysis; Stopped-flow; Transient; Reactive oxygen species; Dioxygen; Superoxide; Hydrogen peroxide

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APA (6^th Edition):

Emerson, J. P. (2014). The kinetics and mechanism of superoxide reduction by two-iron superoxide reductase from Desulfovibrio vulgaris. (Thesis). University of Georgia. Retrieved from http://hdl.handle.net/10724/20776

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Emerson, Joseph Patrick. “The kinetics and mechanism of superoxide reduction by two-iron superoxide reductase from Desulfovibrio vulgaris.” 2014. Thesis, University of Georgia. Accessed March 08, 2021. http://hdl.handle.net/10724/20776.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Emerson, Joseph Patrick. “The kinetics and mechanism of superoxide reduction by two-iron superoxide reductase from Desulfovibrio vulgaris.” 2014. Web. 08 Mar 2021.

Vancouver:

Emerson JP. The kinetics and mechanism of superoxide reduction by two-iron superoxide reductase from Desulfovibrio vulgaris. [Internet] [Thesis]. University of Georgia; 2014. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10724/20776.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Emerson JP. The kinetics and mechanism of superoxide reduction by two-iron superoxide reductase from Desulfovibrio vulgaris. [Thesis]. University of Georgia; 2014. Available from: http://hdl.handle.net/10724/20776

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

15. Vorburger, Pauline. Variations autour d'une porphyrine à anse phénanthroline : un site distal dynamique : Variations on a phenanthroline strapped-porphyrin : evidence of a dynamic distal site.

Degree: Docteur es, Chimie, 2012, Université de Strasbourg

URL: http://www.theses.fr/2012STRAF004

►

L’objectif de ce travail est l’obtention de mimes efficaces d’hémoprotéines telles le cytochrome P450, la myoglobine ou la cytochrome c oxydase, grâce à des variations… (more)

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L’objectif de ce travail est l’obtention de mimes efficaces d’hémoprotéines telles le cytochrome P450, la myoglobine ou la cytochrome c oxydase, grâce à des variations synthétiques autour d’une porphyrine à anse phénanthroline (Porphen). Un nouveau modèle de cytochrome c oxydase a plus particulièrement été analysé ici. Il est préparé par substitution des deux positions meso d’une Zn-Porphen. Des phénomènes dynamiques ont été observés et étudiés par RMN 1H, mettant en évidence la présence d’atropoisomères et la coordination-décoordination de la pyridine proximale sur le zinc. Le remplacement du zinc par du fer a ensuite permis l’étude de la coordination d’un sixième ligand exogène dans un site distal dynamique. L’évolution de la géométrie du complexe a été suivie par spectrophotométrie UV-Visible et RPE. En présence de ligands azotés de type midazoles, il se forme dans tous les cas des complexes [1 récepteur/ 1 substrat]. La forte affinité de notre modèle pour le dioxygène a été montrée à la fois par spectrophotométrie UV-Visible, RMN 1H et par résonance Raman. Que ce soit en UV-Visible ou en RMN, la réversibilité du dioxygène a été montré par son remplacement par du CO. La souplesse de cette nouvelle architecture a été mise en évidence, par l’observation d’une relative flexibilité lors des études par spectroscopie IR de la fixation de CO dans le site distal. Cette adaptabilité est également à l’origine d’un comportement assez surprenant en électrochimie, où la réduction du fer(III) et l’oxydation du cuivre(I) en présence de O2 sont facilitées. En électrocatalyse, la réduction de O2 par ce nouveau modèle de cytochrome c oxydase n’est pas facilitée en terme de potentiel, mais efficace quant à la contribution d’un mécanisme à 4 électrons.

The purpose of this work was to prepare efficient models of cytochrome P450, hemoglobin and cytochrome c oxidase, by various synthetic modifications on a phenanthroline-strapped porphyrin (Porphen). In particular, a new model of cytochrome c oxidase was analyzed here. This compound was obtained by substitution of both meso positions of a Zn-Porphen. Dynamics phenoma were observed and analyzed by 1H NMR, showing the presence of atropoisomers and coordination-decoordination of the proximal pyridine on zinc. Zinc was then replaced by iron, which allows the coordination of a sixth exogenous ligand in the dynamic distal site. The evolution of the complexes’ geometry was monitored by UV-Visible spectrophotometry and EPR. In the presence of imidazolesligands, complexes [1 receptor/ 1 substrate] were observed in all cases. Our model’s high affinity for dioxygen was shown by UV-Visible and 1H NMR spectroscopy and Raman resonance. In UV-Visible and NMR studies, the reversibility of dioxygen binding was demonstrated by replacement with CO.The versatility of this new architecture was demonstrated during IR studies by the relative flexibility of the CO binding in the distal site. This versatility also led to surprisingly behavior in electrochemistry, where the reduction of iron(III) and the…

Advisors/Committee Members: Weiss, Jean (thesis director).

Subjects/Keywords: Hémoprotéines; Chimie biomimétique; Cytochrome c oxydase; Porphyrine; Atropoisomère; Fixation de dioxygène; Electrochimie; Hemoproteins; Biomimetic chemistry; Cytochrome c oxydase; Porphyrin; Atropoisomer; Dioxygen binding; Electrochemistry; 572.7

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vorburger, P. (2012). Variations autour d'une porphyrine à anse phénanthroline : un site distal dynamique : Variations on a phenanthroline strapped-porphyrin : evidence of a dynamic distal site. (Doctoral Dissertation). Université de Strasbourg. Retrieved from http://www.theses.fr/2012STRAF004

Chicago Manual of Style (16^th Edition):

Vorburger, Pauline. “Variations autour d'une porphyrine à anse phénanthroline : un site distal dynamique : Variations on a phenanthroline strapped-porphyrin : evidence of a dynamic distal site.” 2012. Doctoral Dissertation, Université de Strasbourg. Accessed March 08, 2021. http://www.theses.fr/2012STRAF004.

MLA Handbook (7^th Edition):

Vorburger, Pauline. “Variations autour d'une porphyrine à anse phénanthroline : un site distal dynamique : Variations on a phenanthroline strapped-porphyrin : evidence of a dynamic distal site.” 2012. Web. 08 Mar 2021.

Vancouver:

Vorburger P. Variations autour d'une porphyrine à anse phénanthroline : un site distal dynamique : Variations on a phenanthroline strapped-porphyrin : evidence of a dynamic distal site. [Internet] [Doctoral dissertation]. Université de Strasbourg; 2012. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2012STRAF004.

Council of Science Editors:

Vorburger P. Variations autour d'une porphyrine à anse phénanthroline : un site distal dynamique : Variations on a phenanthroline strapped-porphyrin : evidence of a dynamic distal site. [Doctoral Dissertation]. Université de Strasbourg; 2012. Available from: http://www.theses.fr/2012STRAF004

16. Isaac, James Alfred. Conception et synthèse de catalyseurs de cuivre bio-inspirés pour l'activation de liaisons C-H : Design and synthesis of bio-inspired copper catalysts for C-H activation.

Degree: Docteur es, Chimie inorganique et bio inorganique, 2018, Université Grenoble Alpes (ComUE)

URL: http://www.theses.fr/2018GREAV068

►

Les adduits cuivre-oxygène dans les métallo-enzymes ont été proposés comme étant responsables de l'activation de liaisons C-H, processus qui ont un intérêt pour des applications… (more)

▼

Les adduits cuivre-oxygène dans les métallo-enzymes ont été proposés comme étant responsables de l'activation de liaisons C-H, processus qui ont un intérêt pour des applications industrielles potentielles. La première partie de ce travail est consacrée à une présentation de différentes mono-oxygénases à cuivre et de leurs complexes modèles. Récemment, des intermédiaires réactionnels ont émergé et parmi ceux-ci, des espèces de valence mixte CuIICuIII ont été proposées comme étant des espèces réactives clés pour l'activation de liaisons C-H fortes.Dans ce travail, à partir de ligands binucléants basés sur un espaceur 1,8-naphtyridine, la stabilisation et les caractérisations spectroscopiques de ce type d’intermédiaires à haut degré d’oxydation sont explorées. La préparation d’espèces Cu2:O2 à partir de l'activation du dioxygène par les complexes CuI2 est discutée. Deux complexes µ-ɳ2:ɳ2-peroxo-CuII2 ont été préparés à -80°C et caractérisés par différentes méthodes spectroscopiques associées à des calculs par la théorie de la fonctionnelle de la densité (DFT). A partir de nouveaux ligands dissymétriques possédant une fonction amide, nos tentatives pour contrôler la préparation des complexes binucléaires associés sont également présentées. Puis, les caractérisations des espèces à valence mixte CuIICuIII obtenues par mono-oxydation électronique des complexes CuII2 sont décrites (voltammétrie cyclique, résonance paramagnétique électronique, UV-visible, proche infrarouge et DFT).Enfin, ce travail est complété par l’étude de la réactivité des espèces CuIICuIII, pour lesquelles la littérature est presque inexistante. Lorsque des ligands stériquement encombrés sont utilisés dans les espèces à valence mixte, des oxydations intramoléculaires sont observées, alors que l’espèce CuIICuIII possédant un ligand moins encombré oxyde le toluène. Il est à noter que l'ajout d'une base rend le système catalytique.

Copper-oxygen adducts in enzymes have been proposed to be responsible for the activation of C-H bonds, a process that has industrial applications. The first part of this thesis is therefore dedicated to a discussion on various copper oxygenases and their model complexes. Recently, key reactive intermediates have emerged and among them mixed valent CuIICuIII species have been proposed to be responsible for strong C-H bond activation.In this work the stabilisation and spectroscopic characterisation of high valent intermediates using dinucleating ligands based on a 1,8-naphthyridine spacer are explored. The generation of Cu2:O2 species from the activation of O2 by CuI2 complexes is discussed. Two µ-ɳ2:ɳ2-peroxo-CuII2 complexes have been prepared at -80°C and characterised by spectroscopy and density functional theory (DFT). Our attempts at generating dinuclear systems using new dissymmetric ligands with an amide function are also discussed. Finally the successful characterisation of mixed valent CuIICuIII species by mono-electronic oxidation of CuII2 complexes is described (cyclic voltammetry, electron paramagnetic resonance,…

Advisors/Committee Members: Belle, Catherine (thesis director).

Subjects/Keywords: Chimie bio-Inorganique; Ligands; Cuivre; Activation de l’oxygène; Catalyse; Valence mixte; Bio-Inorganic chemistry; Ligands; Copper; Dioxygen activation; Catalysis; Mixed valent species; 540

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Isaac, J. A. (2018). Conception et synthèse de catalyseurs de cuivre bio-inspirés pour l'activation de liaisons C-H : Design and synthesis of bio-inspired copper catalysts for C-H activation. (Doctoral Dissertation). Université Grenoble Alpes (ComUE). Retrieved from http://www.theses.fr/2018GREAV068

Chicago Manual of Style (16^th Edition):

Isaac, James Alfred. “Conception et synthèse de catalyseurs de cuivre bio-inspirés pour l'activation de liaisons C-H : Design and synthesis of bio-inspired copper catalysts for C-H activation.” 2018. Doctoral Dissertation, Université Grenoble Alpes (ComUE). Accessed March 08, 2021. http://www.theses.fr/2018GREAV068.

MLA Handbook (7^th Edition):

Isaac, James Alfred. “Conception et synthèse de catalyseurs de cuivre bio-inspirés pour l'activation de liaisons C-H : Design and synthesis of bio-inspired copper catalysts for C-H activation.” 2018. Web. 08 Mar 2021.

Vancouver:

Isaac JA. Conception et synthèse de catalyseurs de cuivre bio-inspirés pour l'activation de liaisons C-H : Design and synthesis of bio-inspired copper catalysts for C-H activation. [Internet] [Doctoral dissertation]. Université Grenoble Alpes (ComUE); 2018. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2018GREAV068.

Council of Science Editors:

Isaac JA. Conception et synthèse de catalyseurs de cuivre bio-inspirés pour l'activation de liaisons C-H : Design and synthesis of bio-inspired copper catalysts for C-H activation. [Doctoral Dissertation]. Université Grenoble Alpes (ComUE); 2018. Available from: http://www.theses.fr/2018GREAV068

Université de Grenoble

17. Gueneau, Basile. Etude et utilisation de complexes polypyridiniques du cuivre (II) dans le cadre de la catalyse de la délignification des pâtes papetières : Study and use of copper(II) polypyridinic complexes in catalysis of dioxygen delignification of cellulosic pulps.

Degree: Docteur es, Chimie, 2012, Université de Grenoble

URL: http://www.theses.fr/2012GRENV023

►

L’utilisation de dioxygène lors de la délignification des pâtes à papier permet une réduction considérable des coûts de production et de l’impact environnemental du procédé… (more)

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L’utilisation de dioxygène lors de la délignification des pâtes à papier permet une réduction considérable des coûts de production et de l’impact environnemental du procédé de blanchiment. Seulement, le taux de délignification est limité par le fait qu’une partie de la lignine résiduelle n’est pas réactive vis-à-vis du dioxygène et que la cellulose est partiellement dépolymérisée au cours du procédé. L’utilisation de catalyseur pourrait permettre d’améliorer l’efficacité et la sélectivité de la délignification au dioxygène comme le suggèrent certaines études. Le complexe cuivre(II)-phénanthroline présente des résultats prometteurs en termes d’efficacité, mais entraîne une dégradation importante de la cellulose. Différents ligands polypyridiniques ont été étudiés dans ces travaux, afin de trouver un complexe du cuivre(II) présentant une affinité forte vis-à-vis de la lignine et faible vis-à-vis de la cellulose. Les complexes formés ont été caractérisés par spectroscopie UV/Vis et voltammétrie cyclique et étudiés comme catalyseurs de l’oxydation de différents substrats : un composé modèle de lignine non phénolique et des substrats lignocellulosiques (un modèle de cellulose, un modèle de lignine native et une pâte kraft industrielle). Les résultats ont montré que la nature même du ligand a un effet important sur l’activité catalytique du complexe de Cuivre (II) lors de l’oxydation du composé modèle de lignine. En revanche, les complexes actifs présentent une activité faible lors de la délignification d’une pâte kraft et oxydent fortement les hydrates de carbone. Ce manque de sélectivité ne permet pas une application pour la production de pâte à papier mais oriente l’utilisation de ce type de catalyseur dans de nouvelles applications n’ayant pas les mêmes contraintes sur le degré de polymérisation de la cellulose.

Dioxygen delignification considerably reduces the operating cost of the bleaching process and decreases the environmental impact of the bleaching effluent. Unfortunately the performance of dioxygen delignification is limited since part of the residual lignin is not reactive toward dioxygen while cellulose depolymerisation occurs. Studies suggested that dioxygen delignification could be improved thanks to the use of catalysts such as copper(II)–phenanthroline type complexes which have shown promising results on delignification efficiency. However cellulose was also more degraded. Different polypyridinyl ligands have been studied in this work, in an attempt to find copper(II) complexes that have more affinity toward lignin and less toward cellulose. Complexes have been characterised by UV/Vis spectroscopy, cyclic volammetry, and they were studied for the catalysed oxidation of various substrates: a non phenolic lignin model compound and lignocellulosic substrates (a model of cellulose, a model of native lignin and an industrial kraft pulp). It has been shown that the nature of the ligand had a significant effect on the catalytic activity of Cu(II) complexes in the oxygen oxidation of the lignin model compound.…

Advisors/Committee Members: Deronzier, Alain (thesis director), Marlin, Nathalie (thesis director).

Subjects/Keywords: Délignification; Dioxygène; Catalyse; Cuivre; Phénanthroline; Ligands polypyridiniques,; Spectroscopie UV/Vis; Voltammétrie cyclique; Delignification; Dioxygen; Catalysis; Copper; Phenanthroline; Polypyridinyl ligands; UV/Vis spectroscopy; Cyclic voltammetry

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gueneau, B. (2012). Etude et utilisation de complexes polypyridiniques du cuivre (II) dans le cadre de la catalyse de la délignification des pâtes papetières : Study and use of copper(II) polypyridinic complexes in catalysis of dioxygen delignification of cellulosic pulps. (Doctoral Dissertation). Université de Grenoble. Retrieved from http://www.theses.fr/2012GRENV023

Chicago Manual of Style (16^th Edition):

Gueneau, Basile. “Etude et utilisation de complexes polypyridiniques du cuivre (II) dans le cadre de la catalyse de la délignification des pâtes papetières : Study and use of copper(II) polypyridinic complexes in catalysis of dioxygen delignification of cellulosic pulps.” 2012. Doctoral Dissertation, Université de Grenoble. Accessed March 08, 2021. http://www.theses.fr/2012GRENV023.

MLA Handbook (7^th Edition):

Gueneau, Basile. “Etude et utilisation de complexes polypyridiniques du cuivre (II) dans le cadre de la catalyse de la délignification des pâtes papetières : Study and use of copper(II) polypyridinic complexes in catalysis of dioxygen delignification of cellulosic pulps.” 2012. Web. 08 Mar 2021.

Vancouver:

Gueneau B. Etude et utilisation de complexes polypyridiniques du cuivre (II) dans le cadre de la catalyse de la délignification des pâtes papetières : Study and use of copper(II) polypyridinic complexes in catalysis of dioxygen delignification of cellulosic pulps. [Internet] [Doctoral dissertation]. Université de Grenoble; 2012. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2012GRENV023.

Council of Science Editors:

Gueneau B. Etude et utilisation de complexes polypyridiniques du cuivre (II) dans le cadre de la catalyse de la délignification des pâtes papetières : Study and use of copper(II) polypyridinic complexes in catalysis of dioxygen delignification of cellulosic pulps. [Doctoral Dissertation]. Université de Grenoble; 2012. Available from: http://www.theses.fr/2012GRENV023

18. Vo, Nhat Tam. Bioinspired semi-hemic iron(III) complex for chemical and photochemical oxygen atom transfer reactions : Complexe de fer(III) semi-hémique bioinspiré pour les réactions chimiques et photochimiques de transfert d'atome d'oxygène.

Degree: Docteur es, Chimie, 2019, Université Paris-Saclay (ComUE)

URL: http://www.theses.fr/2019SACLS319

►

L’oxydation des hydrocarbures est une transformation chimique difficile aussi bien en biologie qu’en chimie. Les espèces active métal-oxo en de haut degré d’oxydation sont des… (more)

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L’oxydation des hydrocarbures est une transformation chimique difficile aussi bien en biologie qu’en chimie. Les espèces active métal-oxo en de haut degré d’oxydation sont des intermédiaires capables d’effectuer ces transformations. Dans ce manuscrit, nous rapportons la synthèse et la caractérisation d'un complexe de fer (III) supporté par un ligand hémi-porphyrinique non innocent, construit avec un fragment dipyrrine et deux fonctions pyridines. Les complexes de fer (III) ont été préparés et caractérisés, en mettant l'accent sur leur comportement électrochimique et leur utilisation potentielle en tant que catalyseurs pouvant achiver des sources d'oxygène vertes telles que le dioxygène et l'eau en vue d’oxyder des hydrocarbures. Nous avons constaté que ces complexes peuvent catalyser l'oxydation d'une grande variété de substrats en utilisant un agent oxydant tel que l'iodosylbenzène. Curieusement, nos résultats rassemblés suggèrent un schéma de réactivité qui découle d’une espèce de fer de bas degré d’oxydation. Les analyses de résonance paramagnétique électronique et de Mössbauer confirment l'existence d'une espèce réactive de fer (III) haut spin. De plus, les données de spectrométrie de masse et de spectroscopie infrarouge appuyées par des calculs de DFT nous ont aidés à proposer la formulation chimique de cet intermédiaire généré chimiquement où le ligand a été oxydé de manière réversible. En outre, ces complexes ont été utilisés comme catalyseurs dans un système photocatalytique utilisant un accepteur d'électron réversible permettant d'éviter le recours néfaste à un donneur d'électrons sacrificiel. Notre étude fournit un nouveau paradigme pour effectuer des réactions photoinduites de transfert d'atome d'oxygène utilisant la lumière comme la source d'énergie et de l'O₂ comme la source d'atome d'oxygène en solution aqueuse.

Hydrocarbon oxidation is a real challenging chemical transformation both in biology and chemistry. Highly oxidized metal-oxo species are the active intermediates to perform these transformations. In this manuscript we report the synthesis and characterization of an iron(III) complex supported by a non-innocent hemi-porphyrinic ligand, constructed with a dipyrrin fragment and two pyridine functions. The iron(III) complexes have been prepared and characterized, with a focus on their electrochemical behavior and their potential use as catalysts in the activation of green oxygen source such as dioxygen and water for hydrocarbon oxidation. We found that these complexes can catalyze the oxidation of a fair variety of substrates using oxidant agent such as iodosylbenzene. Intriguingly, our gathered results point to a reactivity pattern that stems from a low-oxidation state iron species. Electron Paramagnetic Resonance and Mössbauer analyses support a high spin iron(III) reactive species. Furthermore, data from mass spectrometry and Infra-red spectroscopy supported by DFT calculations helped us to propose the chemical formulation of this chemically generated intermediate where the ligand has been…

Advisors/Committee Members: Aukauloo, Ally (thesis director).

Subjects/Keywords: Complexe de fer; Catalyses; Transfert d’atome d’oxygène; Photo-catalyses; Activation de dioxygène; Transfert de multi-électron; Iron complex; Catalysis; Oxygen atom transfer; Photocatalysis; Dioxygen activation; Multielectron transfer

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Vo, N. T. (2019). Bioinspired semi-hemic iron(III) complex for chemical and photochemical oxygen atom transfer reactions : Complexe de fer(III) semi-hémique bioinspiré pour les réactions chimiques et photochimiques de transfert d'atome d'oxygène. (Doctoral Dissertation). Université Paris-Saclay (ComUE). Retrieved from http://www.theses.fr/2019SACLS319

Chicago Manual of Style (16^th Edition):

Vo, Nhat Tam. “Bioinspired semi-hemic iron(III) complex for chemical and photochemical oxygen atom transfer reactions : Complexe de fer(III) semi-hémique bioinspiré pour les réactions chimiques et photochimiques de transfert d'atome d'oxygène.” 2019. Doctoral Dissertation, Université Paris-Saclay (ComUE). Accessed March 08, 2021. http://www.theses.fr/2019SACLS319.

MLA Handbook (7^th Edition):

Vo, Nhat Tam. “Bioinspired semi-hemic iron(III) complex for chemical and photochemical oxygen atom transfer reactions : Complexe de fer(III) semi-hémique bioinspiré pour les réactions chimiques et photochimiques de transfert d'atome d'oxygène.” 2019. Web. 08 Mar 2021.

Vancouver:

Vo NT. Bioinspired semi-hemic iron(III) complex for chemical and photochemical oxygen atom transfer reactions : Complexe de fer(III) semi-hémique bioinspiré pour les réactions chimiques et photochimiques de transfert d'atome d'oxygène. [Internet] [Doctoral dissertation]. Université Paris-Saclay (ComUE); 2019. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2019SACLS319.

Council of Science Editors:

Vo NT. Bioinspired semi-hemic iron(III) complex for chemical and photochemical oxygen atom transfer reactions : Complexe de fer(III) semi-hémique bioinspiré pour les réactions chimiques et photochimiques de transfert d'atome d'oxygène. [Doctoral Dissertation]. Université Paris-Saclay (ComUE); 2019. Available from: http://www.theses.fr/2019SACLS319

19. Moutet, Jules. Exploration de nouvelles stratégies catalytiques pour le développement de méthodes d'oxydation / oxygénation aérobies : Exploration of new catalytic strategies for the development of O2-promoted oxidizing/oxygenating methodologies.

Degree: Docteur es, Chimie organique, 2017, Université Grenoble Alpes (ComUE)

URL: http://www.theses.fr/2017GREAV076

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Ce travail est consacré à la conception, à la synthèse et à l’étude de catalyseurs d’oxydation à base de métaux 3d en association avec des… (more)

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Ce travail est consacré à la conception, à la synthèse et à l’étude de catalyseurs d’oxydation à base de métaux 3d en association avec des ligands non-innocents. Tout d’abord, le développement de complexes dérivés de deux ligands rédox-actifs tétra-azotés originaux (motifs o-phénylènediamine, aniline et dipyrrine) a été étudié. Plusieurs espèces dans différents états d’oxydation ont été préparées. L’élucidation de leurs structures électroniques a été réalisée par des techniques complémentaires (diffraction des rayons X, électrochimie, spectroscopies UV-Vis-NIR, EPR et Mössbauer). Un complexe de fer biradicalaire basé sur le ligand bis(2-aminophényl)-o-phénylènediamine a été synthétisé. Parallèlement, une architecture innovante bis(2-aminophényl)dipyrrine a été développée. En réaction avec du nickel, du cuivre et du cobalt, elle a conduit à trois complexes isostructuraux présentant un caractère radicalaire anilinyle-dipyrrinyle jamais mis en évidence auparavant. La complexation de cette dipyrrine au manganèse a formé un singulier complexe dinucléaire radicalaire avec une valence mixte inhabituellement localisée sur le ligand.Dans un second temps, les complexes de fer, de cuivre et de manganèse ont été évalués dans des applications d’oxydation. L’étude de la réactivité du biradicalaire de fer a entraîné l’observation d’une espèce à haute valence en spectroscopie Mössbauer. D’autre part, le complexe de cuivre a montré une activité en oxydation d’un alcool. Enfin, une activité en catalyse d’oxygénation aérobie a été identifiée avec le complexe dinucléaire radicalaire de manganèse.

This work is devoted to the design, the synthesis and the study of oxidation catalysts, based on 3d metals and non-innocent ligands. First, the development of complexes derived from two unprecedented tetra-nitrogenated redox-active ligands (o-phenylenediamine, aniline and dipyrrin motifs) has been investigated. A number of species at various oxidation states has been prepared. The elucidation of their electronic structures was performed by complementary techniques (X-Ray diffraction, electrochemistry, UV-Vis-NIR, EPR and Mössbauer spectroscopy). A biradical iron complex based on the bis(2-aminophenyl)-o-phenylenediamine ligand was synthesized. In parallel, an innovative bis(2-aminophenyl)dipyrrin architecture was developed. Its reactions with nickel, copper and cobalt led to three isostructural complexes, showing an unprecedented anilinyl-dipyrrinyl radical character. The complexation of the dipyrrin to manganese afforded a unique dinuclear radical complex with a rare ligand-based mixed valence.In a second phase, iron, copper and manganese complexes were assessed in oxidation applications. The reactivity study of the biradical iron resulted in the observation of a high-valent species thanks to Mössbauer spectroscopy. On the other hand, the copper complex has shown an activity in the oxidation of an alcohol. Finally, a catalytic aerobic activity in oxygenation catalysis was identified with the dinuclear manganese radical complex.

Advisors/Committee Members: Du Moulinet d'Hardemare, Amaury (thesis director).

Subjects/Keywords: Ligands rédox-Actifs; Radicaux azotés; Métaux abondants (Ni; Cu; Co; Fe; Mn); Anilines; O-Phénylènediamines; Réactivité avec le dioxygène; Redox-Active ligands; N-Centered radicals; Earth-Abundant metals (Ni; Cu; Co; Fe; Mn); Anilines; O-Phenylenediamines; Reactivity with dioxygen; 540

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Moutet, J. (2017). Exploration de nouvelles stratégies catalytiques pour le développement de méthodes d'oxydation / oxygénation aérobies : Exploration of new catalytic strategies for the development of O2-promoted oxidizing/oxygenating methodologies. (Doctoral Dissertation). Université Grenoble Alpes (ComUE). Retrieved from http://www.theses.fr/2017GREAV076

Chicago Manual of Style (16^th Edition):

Moutet, Jules. “Exploration de nouvelles stratégies catalytiques pour le développement de méthodes d'oxydation / oxygénation aérobies : Exploration of new catalytic strategies for the development of O2-promoted oxidizing/oxygenating methodologies.” 2017. Doctoral Dissertation, Université Grenoble Alpes (ComUE). Accessed March 08, 2021. http://www.theses.fr/2017GREAV076.

MLA Handbook (7^th Edition):

Moutet, Jules. “Exploration de nouvelles stratégies catalytiques pour le développement de méthodes d'oxydation / oxygénation aérobies : Exploration of new catalytic strategies for the development of O2-promoted oxidizing/oxygenating methodologies.” 2017. Web. 08 Mar 2021.

Vancouver:

Moutet J. Exploration de nouvelles stratégies catalytiques pour le développement de méthodes d'oxydation / oxygénation aérobies : Exploration of new catalytic strategies for the development of O2-promoted oxidizing/oxygenating methodologies. [Internet] [Doctoral dissertation]. Université Grenoble Alpes (ComUE); 2017. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2017GREAV076.

Council of Science Editors:

Moutet J. Exploration de nouvelles stratégies catalytiques pour le développement de méthodes d'oxydation / oxygénation aérobies : Exploration of new catalytic strategies for the development of O2-promoted oxidizing/oxygenating methodologies. [Doctoral Dissertation]. Université Grenoble Alpes (ComUE); 2017. Available from: http://www.theses.fr/2017GREAV076

20. ΔΑΝΟΠΟΥΛΟΣ, ΑΝΔΡΕΑΣ. ΟΞΕΙΔΩΤΙΚΕΣ ΑΝΤΙΔΡΑΣΕΙΣ ΣΥΜΠΛΟΚΩΝ ΠΑΛΛΑΔΙΟΥ ΕΠΙ ΟΛΕΦΙΝΩΝ.

Degree: 1987, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ)

URL: http://hdl.handle.net/10442/hedi/0559

►

REACTION OF [PDCL2(OLEFIN)]2 (OLEFIN=CYCLOHEXENE, CYCLOOCTENE, CYCLOHEPTENE) WITH PDO2(PPH3)2 GIVES THE CORRESPONDING KETONES AS PRODUCTS. REACTION OF THE SAME OLEFIN COMPLEXES WITH PDO2(PPH3)2 IN THE PRESENCE… (more)

Subjects/Keywords: ΔΙΟΞΥΓΕΝΙΚΑ ΣΥΜΠΛΟΚΑ ΠΑΛΛΑΔΙΟΥ; ΚΥΚΛΟΕΞΕΝΙΟ; ΚΥΚΛΟΟΚΤΕΝΙΟ; ΟΛΕΦΙΝΙΚΑ ΣΥΜΠΛΟΚΑ ΠΑΛΛΑΔΙΟΥ; ΠΑΛΛΑΔΙΟ ΕΠΙ ΠΟΛΥΜΕΡΩΝ; CYCLOHEXENE; CYCLOOCTENE; IMMOBILIZED PALLADIUM; PALLADIUM DIOXYGEN COMPLEXES; PALLADIUM OLEFIN COMPLEXES

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

ΔΑΝΟΠΟΥΛΟΣ, . �. (1987). ΟΞΕΙΔΩΤΙΚΕΣ ΑΝΤΙΔΡΑΣΕΙΣ ΣΥΜΠΛΟΚΩΝ ΠΑΛΛΑΔΙΟΥ ΕΠΙ ΟΛΕΦΙΝΩΝ. (Thesis). National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Retrieved from http://hdl.handle.net/10442/hedi/0559

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

ΔΑΝΟΠΟΥΛΟΣ, ΑΝΔΡΕΑΣ. “ΟΞΕΙΔΩΤΙΚΕΣ ΑΝΤΙΔΡΑΣΕΙΣ ΣΥΜΠΛΟΚΩΝ ΠΑΛΛΑΔΙΟΥ ΕΠΙ ΟΛΕΦΙΝΩΝ.” 1987. Thesis, National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ). Accessed March 08, 2021. http://hdl.handle.net/10442/hedi/0559.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

ΔΑΝΟΠΟΥΛΟΣ, ΑΝΔΡΕΑΣ. “ΟΞΕΙΔΩΤΙΚΕΣ ΑΝΤΙΔΡΑΣΕΙΣ ΣΥΜΠΛΟΚΩΝ ΠΑΛΛΑΔΙΟΥ ΕΠΙ ΟΛΕΦΙΝΩΝ.” 1987. Web. 08 Mar 2021.

Vancouver:

ΔΑΝΟΠΟΥΛΟΣ �. ΟΞΕΙΔΩΤΙΚΕΣ ΑΝΤΙΔΡΑΣΕΙΣ ΣΥΜΠΛΟΚΩΝ ΠΑΛΛΑΔΙΟΥ ΕΠΙ ΟΛΕΦΙΝΩΝ. [Internet] [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 1987. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/10442/hedi/0559.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

ΔΑΝΟΠΟΥΛΟΣ �. ΟΞΕΙΔΩΤΙΚΕΣ ΑΝΤΙΔΡΑΣΕΙΣ ΣΥΜΠΛΟΚΩΝ ΠΑΛΛΑΔΙΟΥ ΕΠΙ ΟΛΕΦΙΝΩΝ. [Thesis]. National and Kapodistrian University of Athens; Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών (ΕΚΠΑ); 1987. Available from: http://hdl.handle.net/10442/hedi/0559

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Université Paris-Sud – Paris XI

21. Buron, Charlotte. Développement de nouveaux catalyseurs d’oxydation bioinspirés : greffage de complexes de fer(II) non hémiques sur électrodes d’or ou dans la β-lactoglobuline : Development of novel oxidation bioinspired catalysts : non heme iron(II) complexes grafted on gold electrode or β-lactoglobuline.

Degree: Docteur es, Chimie, 2015, Université Paris-Sud – Paris XI

URL: http://www.theses.fr/2015PA112148

► Dans une thématique de plus en plus importante qui est celle du développement durable, il est aujourd’hui nécessaire d’adapter les réactions chimiques aux contraintes écologiques.… (more)

▼ Dans une thématique de plus en plus importante qui est celle du développement durable, il est aujourd’hui nécessaire d’adapter les réactions chimiques aux contraintes écologiques. Le développement de catalyseurs existe depuis le début de la chimie. Cependant, la compréhension des mécanismes mis en jeu lors des réactions chimiques est beaucoup plus récente, et ce, grâce à l’apparition de techniques d’analyse qui permettent de sonder les systèmes à différentes étapes des réactions. De nombreux catalyseurs moléculaires ont été développés, avec de très bons résultats au niveau des nombres de cycles catalytiques et de la sélectivité des réactions. Toutefois, ces catalyseurs sont souvent constitués d’un centre métallique de type iridium, ruthénium, palladium, rhodium ou platine, qui sont des métaux chers non biocompatibles. D’autre part, les oxydations sont des transformations chimiques très importantes. Des conditions de réactions dures, avec des oxydants stœchiométriques, souvent toxiques ou nocifs, sont généralement utilisées. Au contraire, des systèmes biologiques sont capables d’effectuer l’oxydation de molécules organiques en utilisant le dioxygène de l’air, en présence uniquement de protons, d’électrons, dans des conditions physiologiques. Quel grand défi pour les chimistes que d’arriver à développer des systèmes capables de mimer les systèmes biologiques, avec des catalyseurs composés de métaux biocompatibles tels que le cuivre, le manganèse et le fer. Le développement de ces catalyseurs biomimétiques demande une très bonne compréhension des systèmes biologiques, où les première et seconde sphères de coordination sont primordiales pour l'efficacité et la sélectivité des réactions. De nombreux complexes de fer(II) ont été développés comme catalyseurs dans notre équipe lors de thèses précédentes. L’interaction d’oxydants chimiques avec ces complexes a été étudiée, et une partie de mon projet a été de modifier les ligands pour augmenter la stabilité des catalyseurs, permettant l’augmentation de la sélectivité et les rendements de l’oxydation du cyclohexane et de l’anisole. Deux autres projets ont nécessité la fonctionnalisation d’un ligand utilisé communément au laboratoire pour son greffage covalent sur une électrode d’or ou dans une protéine. Afin de contrôler l’apport d’électrons au centre métallique pour réaliser l'activation réductrice du dioxygène, le complexe fonctionnalisé a été greffé sur des électrodes d’or. Le greffage sur électrode d’or a permis de mettre en avant la formation d’une monocouche homogène. Les premiers tests de réactivité de la SAM avec le dioxygène ont été également effectués. D’autre part, dans le but d’améliorer les rendements ainsi que la sélectivité des réactions en catalyse d’oxydation, un autre complexe fonctionnalisé a été greffé covalemment dans une protéine. Le greffage du complexe dans la β-lactoglobuline a permis de développer une nouvelle méthode de dosage du complexe de fer au sein de la protéine. Il a été possible de générer un intermédiaire réactionnel Feᴵᴵᴵ-peroxo, et les… Advisors/Committee Members: Banse, Frédéric (thesis director).

Subjects/Keywords: Chimie bioinspirée; Activation du dioxygène; Réaction d’oxydation; Chimie de coordination; Oxydation; Cytochrome P450; . β-lactoglobuline; Fer; Greffage covalent; SAM; Métalloenzyme artificielle; Bioinspired chemistry; Dioxygen activation; Oxidation reactions; Coordination chemistry; Oxidation; Cytochrome P450; . β-lactoglobuline; Iron; Covalent grafting; SAM; Artificial metalloenzyme

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Buron, C. (2015). Développement de nouveaux catalyseurs d’oxydation bioinspirés : greffage de complexes de fer(II) non hémiques sur électrodes d’or ou dans la β-lactoglobuline : Development of novel oxidation bioinspired catalysts : non heme iron(II) complexes grafted on gold electrode or β-lactoglobuline. (Doctoral Dissertation). Université Paris-Sud – Paris XI. Retrieved from http://www.theses.fr/2015PA112148

Chicago Manual of Style (16^th Edition):

Buron, Charlotte. “Développement de nouveaux catalyseurs d’oxydation bioinspirés : greffage de complexes de fer(II) non hémiques sur électrodes d’or ou dans la β-lactoglobuline : Development of novel oxidation bioinspired catalysts : non heme iron(II) complexes grafted on gold electrode or β-lactoglobuline.” 2015. Doctoral Dissertation, Université Paris-Sud – Paris XI. Accessed March 08, 2021. http://www.theses.fr/2015PA112148.

MLA Handbook (7^th Edition):

Buron, Charlotte. “Développement de nouveaux catalyseurs d’oxydation bioinspirés : greffage de complexes de fer(II) non hémiques sur électrodes d’or ou dans la β-lactoglobuline : Development of novel oxidation bioinspired catalysts : non heme iron(II) complexes grafted on gold electrode or β-lactoglobuline.” 2015. Web. 08 Mar 2021.

Vancouver:

Buron C. Développement de nouveaux catalyseurs d’oxydation bioinspirés : greffage de complexes de fer(II) non hémiques sur électrodes d’or ou dans la β-lactoglobuline : Development of novel oxidation bioinspired catalysts : non heme iron(II) complexes grafted on gold electrode or β-lactoglobuline. [Internet] [Doctoral dissertation]. Université Paris-Sud – Paris XI; 2015. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2015PA112148.

Council of Science Editors:

Buron C. Développement de nouveaux catalyseurs d’oxydation bioinspirés : greffage de complexes de fer(II) non hémiques sur électrodes d’or ou dans la β-lactoglobuline : Development of novel oxidation bioinspired catalysts : non heme iron(II) complexes grafted on gold electrode or β-lactoglobuline. [Doctoral Dissertation]. Université Paris-Sud – Paris XI; 2015. Available from: http://www.theses.fr/2015PA112148

22. Wijeratne, Bogamuwe Herath Mudiyansele Gayan Bandara. Formation, Characterization, and Oxidative Reactivity of Bio-inspired Peroxo- and Hydroxo-manganese(III) Complexes.

Degree: PhD, Chemistry, 2015, University of Kansas

URL: http://hdl.handle.net/1808/25377

► Manganese-dependent enzymes that react with dioxygen and its reduced derivatives are ubiquitous in nature, catalyzing pivotal processes such as the light-driven oxidation of water to… (more)

▼ Manganese-dependent enzymes that react with dioxygen and its reduced derivatives are ubiquitous in nature, catalyzing pivotal processes such as the light-driven oxidation of water to dioxygen, generation of peroxidized fatty acids, and detoxification of reactive oxygen species such as superoxide and peroxide. Peroxo-, hydroxo-, and oxo-manganese intermediates are often invoked in the mechanisms of a majority of these enzymes. However, detailed understanding of the mechanisms involving Mn-containing enzymes is lacking, warranting further investigations in this area of study. Due to numerous restrictions involved with carrying out such mechanistic studies using the actual proteins of interest, utilization of synthetic bio-inspired model complexes has been a frequent practice. To this end, a series of peroxomanganese(III) complexes with varied steric and electronic properties have been synthesized, and characterized by low-temperature electronic absorption and magnetic circular dichroism (MCD) spectroscopies, as well as complementary density functional theory (DFT) and time-dependent DFT computations. This work resulted in the first report where steric properties of the supporting ligand were shown to play a predominant role in modulating the Mn-peroxo interactions in η2-peroxomanganese(III) intermediates. This study provided intriguing insight into the significance of steric factors of enzymatic active sites in fine-tuning their reactivity properties. Since a majority of peroxomanganese(III) model complexes display impaired thermal stabilities under ambient conditions, designing ligands that minimize their decay pathways is of great interest. This has motivated the design, synthesis, and characterization of such an oxidatively robust supporting ligand, L7BQ (L7BQ = 1,4-di(quinolin-8-yl)-1,4-diazepane), and the characterization of its MnII complex by X-ray diffraction techniques. The corresponding peroxomanganese(III) adduct has been generated and spectroscopically characterized. This adduct exhibits interesting reaction patterns with strong acids and acyl chlorides. Activation of non-prophyrinoid peroxomanganese(III) complexes to generate high-valent oxidants is extremely rare, which makes the reactivity of this new MnIII-O2 adduct highly intriguing. Apart from biological significance, dioxygen activation by MnII centers is of great importance both in environmentally benign synthetic approaches, as well as alternative energy applications such as fuel cells. Several such MnII complexes have been synthesized, and characterized by X-ray diffraction and other techniques. Mechanistic understanding of MnII-mediated dioxygen activation is still in its infancy, although such systems have been successfully utilized in a number of O2-dependent oxidation reactions in generating synthetically desirable organic substrates. We have carried out mechanistic studies of dioxygen activation using electronic absorption, electronic paramagnetic resonance (EPR), and X-ray absorption spectroscopies, in conjugation with mass spectrometric and… Advisors/Committee Members: Jackson, Timothy A (advisor), https://orcid.org/0000-0001-7609-6406 (advisor), Barybin, Mikhail V (cmtemember), Tunge, Jon A (cmtemember), Benson, David R (cmtemember), Leonard, Kevin C (cmtemember).

Subjects/Keywords: Chemistry; dioxygen activation; hydroxomanganese; O-H bond oxidation; peroxomanganese; proton coupled electron transfer reactivity; saturation kinetics

…x29; Complexes 1.5. Dioxygen Activation to Generate MnIII-OH Complexes 1.6. References… …Oxidation by a Mononuclear Mn(III)OH Complex Derived from Dioxygen 4.1. Introduction… …Dioxygen Activation Pathways of Monomeric Manganese(II) Complexes Appendix 6.1… …with dioxygen and all its reduced derivatives (superoxide, peroxide and oxide)… …deoxyribonucleotides,18 peroxidation of fatty acids,5-8 and water oxidation to dioxygen within biological…

11 more images…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wijeratne, B. H. M. G. B. (2015). Formation, Characterization, and Oxidative Reactivity of Bio-inspired Peroxo- and Hydroxo-manganese(III) Complexes. (Doctoral Dissertation). University of Kansas. Retrieved from http://hdl.handle.net/1808/25377

Chicago Manual of Style (16^th Edition):

Wijeratne, Bogamuwe Herath Mudiyansele Gayan Bandara. “Formation, Characterization, and Oxidative Reactivity of Bio-inspired Peroxo- and Hydroxo-manganese(III) Complexes.” 2015. Doctoral Dissertation, University of Kansas. Accessed March 08, 2021. http://hdl.handle.net/1808/25377.

MLA Handbook (7^th Edition):

Wijeratne, Bogamuwe Herath Mudiyansele Gayan Bandara. “Formation, Characterization, and Oxidative Reactivity of Bio-inspired Peroxo- and Hydroxo-manganese(III) Complexes.” 2015. Web. 08 Mar 2021.

Vancouver:

Wijeratne BHMGB. Formation, Characterization, and Oxidative Reactivity of Bio-inspired Peroxo- and Hydroxo-manganese(III) Complexes. [Internet] [Doctoral dissertation]. University of Kansas; 2015. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1808/25377.

Council of Science Editors:

Wijeratne BHMGB. Formation, Characterization, and Oxidative Reactivity of Bio-inspired Peroxo- and Hydroxo-manganese(III) Complexes. [Doctoral Dissertation]. University of Kansas; 2015. Available from: http://hdl.handle.net/1808/25377

University of Maryland

23. Khusnutdinova, Julia. LIGAND-ENABLED PLATINUM – CARBON BOND FUNCTIONALIZATION UTILIZING DIOXYGEN AS THE TERMINAL OXIDANT.

Degree: Chemistry, 2009, University of Maryland

URL: http://hdl.handle.net/1903/9265

► The use of organotransition metal complexes for selective functionalization of hydrocarbons is of great importance. Dioxygen is the most practical oxidant for large-scale applications in… (more)

Subjects/Keywords: Chemistry, Inorganic; C-O reductive elimination; dioxygen; oxetane; oxidation; platinum; Pt-C bond functionalization

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Khusnutdinova, J. (2009). LIGAND-ENABLED PLATINUM – CARBON BOND FUNCTIONALIZATION UTILIZING DIOXYGEN AS THE TERMINAL OXIDANT. (Thesis). University of Maryland. Retrieved from http://hdl.handle.net/1903/9265

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Khusnutdinova, Julia. “LIGAND-ENABLED PLATINUM – CARBON BOND FUNCTIONALIZATION UTILIZING DIOXYGEN AS THE TERMINAL OXIDANT.” 2009. Thesis, University of Maryland. Accessed March 08, 2021. http://hdl.handle.net/1903/9265.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Khusnutdinova, Julia. “LIGAND-ENABLED PLATINUM – CARBON BOND FUNCTIONALIZATION UTILIZING DIOXYGEN AS THE TERMINAL OXIDANT.” 2009. Web. 08 Mar 2021.

Vancouver:

Khusnutdinova J. LIGAND-ENABLED PLATINUM – CARBON BOND FUNCTIONALIZATION UTILIZING DIOXYGEN AS THE TERMINAL OXIDANT. [Internet] [Thesis]. University of Maryland; 2009. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/1903/9265.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Khusnutdinova J. LIGAND-ENABLED PLATINUM – CARBON BOND FUNCTIONALIZATION UTILIZING DIOXYGEN AS THE TERMINAL OXIDANT. [Thesis]. University of Maryland; 2009. Available from: http://hdl.handle.net/1903/9265

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

24. Brugnara, Andrea. Contrôle cavitaire de la réactivité redox d'un ion métallique (Cu) dans un environnement biomimétique : Supramolecular redox control of a biomimetic metallo-site (Cu) embedded in a cavity.

Degree: Docteur es, Chimie, 2013, Université Paris Descartes – Paris V

URL: http://www.theses.fr/2013PA05P625

►

La molécule X6TMPA, constituée d’une unité TMPA (tris(2-pyridylméthyl)amine) greffée de façon covalente à trois des six unités aromatiques du calix[6]arène, permet de coordiner et stabiliser… (more)

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La molécule X6TMPA, constituée d’une unité TMPA (tris(2-pyridylméthyl)amine) greffée de façon covalente à trois des six unités aromatiques du calix[6]arène, permet de coordiner et stabiliser un ion cuivre (Cu+ et Cu2+) dans un environnement mononucléaire. Ces composés possèdent des propriétés uniques en chimie hôte-invité ainsi qu’en réactivité redox. De tels systèmes présentent cependant des limitations car : – le macrocycle et les complexes métalliques associés ne sont solubles qu’en milieu organique ; – le complexe cuivreux obtenu avec un tel macrocycle n’est réactif vis-à-vis de l’oxygène qu’à l’état solide. Le présent travail de thèse décrit les modifications introduites dans la structure du composé X6TMPA pour faire face à ces restrictions, détaillant ainsi les études conduites afin d’évaluer l’impact des modifications sur les propriétés des molécules résultantes. Le chapitre 2 présente la stratégie synthétique de « trifonctionnalisation » du grand col du macrocycle. Elle a été employée pour l’introduction de groupements hydrophiles, qui rendent le calix[6]arène et les complexes métalliques associés solubles en milieu aqueux. Des études de reconnaissance moléculaire en solution aqueuse ont été ainsi menées. Une propriété très remarquable en chimie hôte-invité est la forte affinité du complexe cuivrique pour l’anion fluorure en milieu aqueux. Le chapitre 3 présente la stratégie synthétique de « hexafonctionnalisation » du grand col du macrocycle. Elle a permis d’obtenir des composés qui ont été utilisés pour des applications telles que l’immobilisation sur surface et la réaction de monoclick. Le chapitre 4 présente la stratégie synthétique de « trifonctionnalisation » du petit col du macrocycle. Elle a permis d’obtenir des systèmes réactifs en solution, notamment un composé contenant trois unités phénol qui donne un radical stable à température ambiante ainsi qu’un composé contenant trois unités quinone dans lequel la cavité est devenue une unité redox-active. Ainsi, des études concernant les macrocycles et leurs complexes monométalliques à base de Zn2+, Cu+ et Cu2+ sont exposées et discutées.

The X6TMPA molecule is composed by a tris(2-pyridylmethyl)amine (TMPA) cap covalently linked to the small rim of the calix[6]arene. This compound can coordinate and stabilize a Cu(I)/Cu(II) ion in a mononuclear environment. These compounds possess unique properties in host-guest and redox chemistry.This PhD thesis work describes some synthetic strategies employed in order to modify the scaffold of the macrocycle, either at the large or the small rim. Moreover, the studies conducted in order to evaluate the impact of each structural modification on the reactivity of the resulting system are detailed. Chapter 2 describes the “large rim tri-functionalization” strategy. It has been employed to introduce three hydrophilic moieties on the calix[6]arene unit. These groups enable the water-solubilization of the molecule, as well as the Cu(I)/Cu(II) monometallic complexes. For these systems, host-guest chemistry in aqueous media…

Advisors/Committee Members: Reinaud, Olivia (thesis director).

Subjects/Keywords: Calix[6]arène; Calix[6]azacryptand; Fonctionnalisation calix[6]arène; Hydrosolubilisation; Immobilisation sur surface; Calix[6]quinone; Cuivre; Zinc; Confinement cavitaire; Chimie hôte-invité; Radical phénoxyle; Activation dioxygène; Biomimétisme; Calix[6]arene; Calix[6]azacryptand; Calix[6]arene functionalization; Water-solubilizaton; Surface functionalization; Calix[6]quinone; Copper; Zinc; Host-guest chemistry; Phenoxyl radical; Dioxygen activation; Biomimetic model; 547.056 52

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APA (6^th Edition):

Brugnara, A. (2013). Contrôle cavitaire de la réactivité redox d'un ion métallique (Cu) dans un environnement biomimétique : Supramolecular redox control of a biomimetic metallo-site (Cu) embedded in a cavity. (Doctoral Dissertation). Université Paris Descartes – Paris V. Retrieved from http://www.theses.fr/2013PA05P625

Chicago Manual of Style (16^th Edition):

Brugnara, Andrea. “Contrôle cavitaire de la réactivité redox d'un ion métallique (Cu) dans un environnement biomimétique : Supramolecular redox control of a biomimetic metallo-site (Cu) embedded in a cavity.” 2013. Doctoral Dissertation, Université Paris Descartes – Paris V. Accessed March 08, 2021. http://www.theses.fr/2013PA05P625.

MLA Handbook (7^th Edition):

Brugnara, Andrea. “Contrôle cavitaire de la réactivité redox d'un ion métallique (Cu) dans un environnement biomimétique : Supramolecular redox control of a biomimetic metallo-site (Cu) embedded in a cavity.” 2013. Web. 08 Mar 2021.

Vancouver:

Brugnara A. Contrôle cavitaire de la réactivité redox d'un ion métallique (Cu) dans un environnement biomimétique : Supramolecular redox control of a biomimetic metallo-site (Cu) embedded in a cavity. [Internet] [Doctoral dissertation]. Université Paris Descartes – Paris V; 2013. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2013PA05P625.

Council of Science Editors:

Brugnara A. Contrôle cavitaire de la réactivité redox d'un ion métallique (Cu) dans un environnement biomimétique : Supramolecular redox control of a biomimetic metallo-site (Cu) embedded in a cavity. [Doctoral Dissertation]. Université Paris Descartes – Paris V; 2013. Available from: http://www.theses.fr/2013PA05P625

25. Kittredge, Clive Tristan. Electron Transfer Studies Of Bacterial Cytochrome And Quinol Oxidases Using Time-Resolved Optical Absorption Spectroscopy.

Degree: Chemistry, 2013, University of California – Santa Cruz

URL: http://www.escholarship.org/uc/item/40x4g07j

► Insight into the mechanism of intramolecular electron transfer and ligand access in the heme-copper oxidases during O₂ reduction is fundamental to understanding how the protein… (more)

Subjects/Keywords: Biochemistry; Biophysics; Chemistry; Cytochrome Oxidase; Dioxygen Reduction Mechanism; Electron Transfer; Ligand Channel Access; Quinol Oxidase; Time-Resolved Optical Absorption Spectroscopy

…reaction of the dioxygen with the mixed-valence E. coli bo3 ............................. 44… …oxidase superfamily. The enzyme catalyzes the reduction of dioxygen to water, which is coupled… …family of enzymes couples the catalysis of dioxygen reduction to water (Equation 1)… …sphaeroides. Mechanism of dioxygen reduction to water by heme-copper oxidases. The postulated… …reduction of dioxygen to water in E. coli bo3 has been postulated to be analogous to the mechanism…

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APA (6^th Edition):

Kittredge, C. T. (2013). Electron Transfer Studies Of Bacterial Cytochrome And Quinol Oxidases Using Time-Resolved Optical Absorption Spectroscopy. (Thesis). University of California – Santa Cruz. Retrieved from http://www.escholarship.org/uc/item/40x4g07j

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kittredge, Clive Tristan. “Electron Transfer Studies Of Bacterial Cytochrome And Quinol Oxidases Using Time-Resolved Optical Absorption Spectroscopy.” 2013. Thesis, University of California – Santa Cruz. Accessed March 08, 2021. http://www.escholarship.org/uc/item/40x4g07j.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kittredge, Clive Tristan. “Electron Transfer Studies Of Bacterial Cytochrome And Quinol Oxidases Using Time-Resolved Optical Absorption Spectroscopy.” 2013. Web. 08 Mar 2021.

Vancouver:

Kittredge CT. Electron Transfer Studies Of Bacterial Cytochrome And Quinol Oxidases Using Time-Resolved Optical Absorption Spectroscopy. [Internet] [Thesis]. University of California – Santa Cruz; 2013. [cited 2021 Mar 08]. Available from: http://www.escholarship.org/uc/item/40x4g07j.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kittredge CT. Electron Transfer Studies Of Bacterial Cytochrome And Quinol Oxidases Using Time-Resolved Optical Absorption Spectroscopy. [Thesis]. University of California – Santa Cruz; 2013. Available from: http://www.escholarship.org/uc/item/40x4g07j

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

26. Mahinthichaichan, Paween. Microscopic description of gas permeation and delivery pathways in biological macromolecules.

Degree: PhD, Biochemistry, 2016, University of Illinois – Urbana-Champaign

URL: http://hdl.handle.net/2142/95310

► Life on Earth fundamentally and indispensably relies on proper regulation and metabolism of inorganic molecules such as dioxygen (O2), nitric oxide (NO), carbon dioxide (CO2)… (more)

▼ Life on Earth fundamentally and indispensably relies on proper regulation and metabolism of inorganic molecules such as dioxygen (O2), nitric oxide (NO), carbon dioxide (CO2) and ammonia (NH3). These chemical species often act as substrates of enzymes and/or as ligands modulating biochemical cascades, so elucidating their delivery and transport is imminent towards understanding cellular functions. Destinated targets (i.e. proteins and enzymes) of these molecules are often separated from exterior environments by layers or shells coated not only membrane lipids but also, in some cases, proteins, effectively forming physical barriers against their passage. For instance, catalytic site of many enzymes are sequestered deeply inside, while there is no clearly defined pathways for substrate delivery and product removal. Since gaseous molecules such as O2, NO, CO2 and NH3 have tiny volumes, probing their interactions with their surroundings within a medium requires techniques that provide both atomic spatial and small temporal resolutions. To fulfill these purposes, I have employed molecular dynamics (MD) simulation to characterize delivery pathways of O2, NO and CO2 in aerobic respiratory terminal oxidases (cytochrome ba3 and cytochrome aa3), nitric oxide reductase (cNOR) and bacterial carboxysome, and to describe the movement of O2, CO2 and NH3 through lipid membranes and membrane channels. In the first part of this dissertation, I illustrated the necessity of pathways in assuring optimal delivery of O2 or NO to the terminal oxidases and cNOR, which are homologous enzymes, under physiological conditions. The conclusions from the studies are correlated to the experimental measurements. Although O2 and NO are readily dissolved in membrane lipids, they migrate to the reduction site exclusively via a pre-formed hydrophobic tunnel. The unobstructed pathway in cytochrome ba3 ultimately permits the substrate(s) to migrate at the maximum diffusion rate (10⁹ M^−1 s^−1), which is faster than through partially constricted pathways in cytochrome aa3 and cNOR. I then characterized the permeation of CO2 fixation substrates through the carboxysome shell of cyanobacteria, which is an assembled layer of shell proteins. The results of energetic analysis characterized a pore within each shell protein to be permeable to bicarbonate (HCO3- ) rather than CO2 and O2. The preferred uptake of HCO3- is advantageous of enhancing the incorporation of CO2 into biomass and mitigating the wasteful O2 fixation. The enzyme carbonic anhydrase inside the carboxysomal lumen can readily convert HCO3- to CO2. In the second part of this dissertation, I examined the permeability of O2 and CO2 across lipid membranes varied by ratios of glycerolphospholipids, cholesterol and sphinogomyelins, which are major constituents of mammalian membranes. This study shows that membrane lipid compositions modulate the permeability of nonpolar gases, emphasizing the existence of gas-impermeable membranes and significance of membrane-facilitated gas channels. I have also… Advisors/Committee Members: Tajkhorshid, Emad (advisor), Tajkhorshid, Emad (Committee Chair), Gennis, Robert B (Committee Chair), Crofts, Antony R (committee member), Grosman, Claudio F (committee member).

Subjects/Keywords: Molecular dynamic simulation; Enhanced sampling techniques; Free energy calculations; Gas permeation and transport; Dioxygen; Nitric oxide; Carbon dioxide; Ammonia; Bicarbonate and ions; Proteins; Enzymes; Ligands; Substrates; Hydrophobic tunnels; Bioenergetics; Aerobic respiration; Terminal oxidases; Bacterial denitrification; nitric oxide reductases; Carbon dioxide fixation; Bacterial carboxysome; Membrane permeability; Glycerophospholipids; Cholesterol; Sphingomyelin; Aquaporins; Aquaglyceroporins

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APA (6^th Edition):

Mahinthichaichan, P. (2016). Microscopic description of gas permeation and delivery pathways in biological macromolecules. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/95310

Chicago Manual of Style (16^th Edition):

Mahinthichaichan, Paween. “Microscopic description of gas permeation and delivery pathways in biological macromolecules.” 2016. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed March 08, 2021. http://hdl.handle.net/2142/95310.

MLA Handbook (7^th Edition):

Mahinthichaichan, Paween. “Microscopic description of gas permeation and delivery pathways in biological macromolecules.” 2016. Web. 08 Mar 2021.

Vancouver:

Mahinthichaichan P. Microscopic description of gas permeation and delivery pathways in biological macromolecules. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2016. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/2142/95310.

Council of Science Editors:

Mahinthichaichan P. Microscopic description of gas permeation and delivery pathways in biological macromolecules. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2016. Available from: http://hdl.handle.net/2142/95310

27. De Leener, Gaël. Nouveaux complexes biomimétiques dérivés de calix[6]azacryptands : étude des effets de seconde sphère et greffage sur surface : New biomimetic complexes derived from calix[6]azacryptands : study of second sphere effects and surface functionalization.

Degree: Docteur es, Chimie organique, 2016, Sorbonne Paris Cité; Université libre de Bruxelles (1970-....)

URL: http://www.theses.fr/2016USPCB024

► Plus de 30% des enzymes présentent un ion métallique dans leur site actif qui est la clé pour les réactions de catalyse. Une sous-famille d’enzymes… (more)

▼ Plus de 30% des enzymes présentent un ion métallique dans leur site actif qui est la clé pour les réactions de catalyse. Une sous-famille d’enzymes comporte un site actif où un seul ion métallique (Zn2+ ou Cun+) est coordiné à un cœur polyhistidine. L’élaboration de composés modèles est important pour la compréhension des mécanismes fondamentaux impliqués dans le cycle biocatalytique de ces enzymes mononucléaires. Dans ce contexte, nous avons développé des ligands basés sur des calix[6]arènes présentant un chapeau polyazoté lié de manière covalente au macrocycle. Ces ligands offrent un site de coordination pour le métal et une cavité hydrophobe bien définie. Cet assemblage permet et contrôle la liaison d’un ligand exogène dans la cavité. Afin de moduler les propriétés des complexes métalliques calixaréniques basés sur une unité coordinante tren (tris(2-aminoéthyl)amine), nous avons synthétisé avec succès et étudié plusieurs nouveaux récepteurs calix[6]aréniques. La synthèse de récepteurs bisétagés, le calix[6]amido-tren et le calix[6]amido-tacn, a permis de modifier la seconde sphère de coordination par incorporation de groupements amide entre la cavité et le site de coordination. Cette stratégie s’est avérée efficace. En effet, la coordination d’anions au centre métallique a été mise en évidence et en particulier celle simultanée de deux Cl¯ pour le Cu-calix[6]amido-tren. Cette coordination d’un ou plusieurs invités anioniques était impossible dans le cas du calix[6]tren parent qui présente une seconde sphère de coordination électroniquement dense et un chapeau trop petit pour y accueillir plusieurs invités. La présence de groupements carbonyle entre la chapeau tren et le calixarène modifie également le comportement des complexes : leur coordination au centre métallique entre en compétition avec celle d’invités exogènes. L’oxydation d’amines encombrées sous O2 en hydroxylamines et oximes a été réalisée par la réduction du complexe cuivrique du calix[6]amido-tren par électrochimie. Ce type d’amines n’est pas oxydable par l’adduit superoxo du complexe parent, dû à la taille de la cavité qui empêche la coordination d’invités encombrés. De plus, la formation d’un adduit superoxo a été mise en évidence qualitativement au départ du complexe cuivreux isolé de ce même composé. Ces résultats permettent d’envisager des études de réactivité mimant le site actif des enzymes PHM et DβM par exemple. Enfin, une comparaison des propriétés hôte-invité et de la réactivité des complexes du calix[6]amido-tren avec celles des complexes du calix[6]amido-tacn a été réalisée afin d’évaluer l’impact de la nature du chapeau polyazoté sur les propriétés hôte-invité et la réactivité de ces complexes. Une méthodologie de déméthylation assistée de manière supramoléculaire a été développée pour différents calix[6]azacryptands chapeautés. Celle-ci a ensuite été appliquée avec succès à la déméthylation du calix[6]tren pour obtenir le calix[6]trentrisPhOH. Ce récepteur a montré un comportement très différent de celui du récepteur parent. En effet,… Advisors/Committee Members: Reinaud, Olivia (thesis director), Jabin, Ivan (thesis director).

Subjects/Keywords: Calix[6]arène; Calix[6]azacryptand; Fonctionnalisation calix[6]arène; Immobilisation sur surface; Hydrosolubilisation; Calix[6]tren; Cuivre; Zinc; Effets de seconde sphère; Bisétagé; Chimie hôte-invité; Radical phénoxyle; Activation dioxygène; Biomimétisme; Calix[6]arene; Calix[6]azacryptand; Calix[6]arene functionalization; Surface functionalization; Water-solubilization; Calix[6]tren; Copper; Zinc; Host-guest chemistry; Second sphere effects; Phenoxyl radical; Dioxygen activation; Biomimicry; 547.122 6

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

De Leener, G. (2016). Nouveaux complexes biomimétiques dérivés de calix[6]azacryptands : étude des effets de seconde sphère et greffage sur surface : New biomimetic complexes derived from calix[6]azacryptands : study of second sphere effects and surface functionalization. (Doctoral Dissertation). Sorbonne Paris Cité; Université libre de Bruxelles (1970-....). Retrieved from http://www.theses.fr/2016USPCB024

Chicago Manual of Style (16^th Edition):

De Leener, Gaël. “Nouveaux complexes biomimétiques dérivés de calix[6]azacryptands : étude des effets de seconde sphère et greffage sur surface : New biomimetic complexes derived from calix[6]azacryptands : study of second sphere effects and surface functionalization.” 2016. Doctoral Dissertation, Sorbonne Paris Cité; Université libre de Bruxelles (1970-....). Accessed March 08, 2021. http://www.theses.fr/2016USPCB024.

MLA Handbook (7^th Edition):

De Leener, Gaël. “Nouveaux complexes biomimétiques dérivés de calix[6]azacryptands : étude des effets de seconde sphère et greffage sur surface : New biomimetic complexes derived from calix[6]azacryptands : study of second sphere effects and surface functionalization.” 2016. Web. 08 Mar 2021.

Vancouver:

De Leener G. Nouveaux complexes biomimétiques dérivés de calix[6]azacryptands : étude des effets de seconde sphère et greffage sur surface : New biomimetic complexes derived from calix[6]azacryptands : study of second sphere effects and surface functionalization. [Internet] [Doctoral dissertation]. Sorbonne Paris Cité; Université libre de Bruxelles (1970-....); 2016. [cited 2021 Mar 08]. Available from: http://www.theses.fr/2016USPCB024.

Council of Science Editors:

De Leener G. Nouveaux complexes biomimétiques dérivés de calix[6]azacryptands : étude des effets de seconde sphère et greffage sur surface : New biomimetic complexes derived from calix[6]azacryptands : study of second sphere effects and surface functionalization. [Doctoral Dissertation]. Sorbonne Paris Cité; Université libre de Bruxelles (1970-....); 2016. Available from: http://www.theses.fr/2016USPCB024

Brno University of Technology

28. Podal, Pavel. Studium vlastností katalyzátoru na bázi MnOx s využitím RRDE: Study of MnOx properties using RRDE.

Degree: 2019, Brno University of Technology

URL: http://hdl.handle.net/11012/8306

► This master thesis deals with qualifications of the catalytic materials for positive electrode low-temperature fuel cells. The teoretical part focuses on the physical and chemical… (more)

Subjects/Keywords: Palivový článek; nízkoteplotní palivový článek; oxid manganičitý; elektrochemie; lineární voltametrie; cyklická voltametrie; hydrodynamické metody; rotační disková elektroda; RDE; rotační disková elektroda s prstencem; RRDE; příprava katalyzátoru na bázi MnOx; aktivita katalyzátoru; koeficient sběrné účinnosti; redukce kyslíku.; Fuel cell; low-temperature fuel cell; manganese dioxide; electrochemistry; linear voltammetry; cyclic voltametry; hydrodynamic methods; rotation disc electrode; RDE; rotation ring disk electrode; RRDE; preparation catalyzer MnOx base; catalyst's activity; collection efficiency; reduction of dioxygen.

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Podal, P. (2019). Studium vlastností katalyzátoru na bázi MnOx s využitím RRDE: Study of MnOx properties using RRDE. (Thesis). Brno University of Technology. Retrieved from http://hdl.handle.net/11012/8306

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Podal, Pavel. “Studium vlastností katalyzátoru na bázi MnOx s využitím RRDE: Study of MnOx properties using RRDE.” 2019. Thesis, Brno University of Technology. Accessed March 08, 2021. http://hdl.handle.net/11012/8306.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Podal, Pavel. “Studium vlastností katalyzátoru na bázi MnOx s využitím RRDE: Study of MnOx properties using RRDE.” 2019. Web. 08 Mar 2021.

Vancouver:

Podal P. Studium vlastností katalyzátoru na bázi MnOx s využitím RRDE: Study of MnOx properties using RRDE. [Internet] [Thesis]. Brno University of Technology; 2019. [cited 2021 Mar 08]. Available from: http://hdl.handle.net/11012/8306.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Podal P. Studium vlastností katalyzátoru na bázi MnOx s využitím RRDE: Study of MnOx properties using RRDE. [Thesis]. Brno University of Technology; 2019. Available from: http://hdl.handle.net/11012/8306

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

29. Saracini, Claudio. CARBON MONOXIDE AND DIOXYGEN PHOTO-RELEASE, BINDING KINETICS, AND THERMODYNAMICS IN 1:1 MONONUCLEAR AND 2:1 DINUCLEAR COPPER/DIOXYGEN COMPLEXES.

Degree: 2014, Johns Hopkins University

URL: http://jhir.library.jhu.edu/handle/1774.2/37054

► Enzymes where the active site contains one or more copper ions catalyze a wide range of organic substrate transformations in Nature. The structures and function… (more)

▼ Enzymes where the active site contains one or more copper ions catalyze a wide range of organic substrate transformations in Nature. The structures and function of such active sites have been finely tuned by evolution to reach the point where dioxygen binding, activation, and utilization for oxidative chemistry has become finely modulated. As is overviewed in Chapter 1, it is useful to categorize the enzymes supported by two copper centers in their active sites as 'uncoupled' (i.e. in peptidylglycine -hydroxylating monooxygenase (PHM) and in dopamine -monooxygenase (DM)) or 'coupled' (i.e. in tyrosinase (Tyr) and in catechol oxidase (Co)) on the basis of the spatial proximity of the two metals in the three-dimensional matrix of the protein. This proximity has profound effects on the chemistry displayed by these two classes of enzymes. Importantly, dioxygen binding to the copper centers is the first step of the catalytic cycle in all of these systems. However, both mononuclear 1:1 and dinuclear 2:1 copper/O2 adducts forming in the enzymes have been shown to be unstable and their detection and their study has been difficult. As it is also discussed in Chapter 1, low temperature spectroscopic techniques together with synthetic model chemistry have come into play and greatly improved our understanding of the mechanistic details involved in such kinds of reactivity. In this work, laser flash-photolysis techniques in combination with copper-synthetic model chemistry have been employed to help the elucidation of fundamental physical and chemical properties of copper/O2 coordination and dynamics. One of the methods that has been successfully employed to study labile copper/dioxygen adducts is laser flash-photolysis of synthetic (L)copper(I)-CO compounds (L =ligand) in the presence of O2 in organic solvents. In Chapter 2, a flash-photolysis study of tridentate N-donor ligand-copper(I)-CO complexes is presented using such techniques. The implications of tricoordination vs. tetracoordination of copper ion on the dynamics of CO and O2 binding to the metal are discussed for these metal complexes. Tricoordinate environments are more similar in their coordination sphere with those present in the enzymes, as compared to their tetracoordinated synthetic counterparts. In Chapter 3, a new method to study copper/dioxygen binding for mononuclear copper complexes is presented. The previously employed carbon monoxide utilization to start from stable (L)copper(I)-CO complexes is bypassed, in this work, by affording direct O2 photo-release from relatively stable mononuclear copper(II)-superoxide complexes. Interestingly, a different quantum yield for O2 release was found depending on the excitation wavelength used and in collaborative efforts, this effect has been investigated by means of Time-Dependent Density Functional Theory (TD-DFT) studies. This work was further extended and presented in Chapter 4, where the same technique was employed for dinuclear 2:1 Cu/O2 synthetic adducts with a peroxo fragment bound in a side-on mode to the… Advisors/Committee Members: Karlin, Kenneth D (advisor).

Subjects/Keywords: Oxygen activation; coupled copper enzymes; uncoupled copper enzymes; mononuclear and dinuclear copper?O2 adducts; copper synthetic model chemistry; laser flash-photolysis; physical properties; transient absorption spectroscopy; carbon monoxide; dioxygen; tricoordinate; tetracoordinate; flash-and-trap method; copper(II)-superoxide; dicopper(II) peroxo; quantum yield; excitation wavelength; TD-DFT; end-on; side-on; irradiation; visible light; one-photon two-electron; oxidation; hydrogen atom abstraction; reversible; thermodynamics; kinetics; kinetic relaxation model; pseudo-first-order; second-order; rate constant; binding dynamics; tyrosinase; hemocyanin; catechol oxidase; PHM; DBM; irradiation; laser.

…dioxygen (as peroxide) to the dicopper site and (ii) the C2His/S-Cys… …x5B;CuI(TMPA)(MeCN)]+ and dioxygen at low temperature. 24 Figure… …CuII-O2 ��CuI (a). Direct observation of such an intermediate came from dioxygen… …x28;209 M) at -80 0C, to give a dioxygen adduct (bis--oxo-dicopper(III) or… …x27;. 145 Scheme 1. One-photon two-electron oxidation of peroxide to dioxygen. 136…

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APA (6^th Edition):

Saracini, C. (2014). CARBON MONOXIDE AND DIOXYGEN PHOTO-RELEASE, BINDING KINETICS, AND THERMODYNAMICS IN 1:1 MONONUCLEAR AND 2:1 DINUCLEAR COPPER/DIOXYGEN COMPLEXES. (Thesis). Johns Hopkins University. Retrieved from http://jhir.library.jhu.edu/handle/1774.2/37054

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Saracini, Claudio. “CARBON MONOXIDE AND DIOXYGEN PHOTO-RELEASE, BINDING KINETICS, AND THERMODYNAMICS IN 1:1 MONONUCLEAR AND 2:1 DINUCLEAR COPPER/DIOXYGEN COMPLEXES.” 2014. Thesis, Johns Hopkins University. Accessed March 08, 2021. http://jhir.library.jhu.edu/handle/1774.2/37054.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Saracini, Claudio. “CARBON MONOXIDE AND DIOXYGEN PHOTO-RELEASE, BINDING KINETICS, AND THERMODYNAMICS IN 1:1 MONONUCLEAR AND 2:1 DINUCLEAR COPPER/DIOXYGEN COMPLEXES.” 2014. Web. 08 Mar 2021.

Vancouver:

Saracini C. CARBON MONOXIDE AND DIOXYGEN PHOTO-RELEASE, BINDING KINETICS, AND THERMODYNAMICS IN 1:1 MONONUCLEAR AND 2:1 DINUCLEAR COPPER/DIOXYGEN COMPLEXES. [Internet] [Thesis]. Johns Hopkins University; 2014. [cited 2021 Mar 08]. Available from: http://jhir.library.jhu.edu/handle/1774.2/37054.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Saracini C. CARBON MONOXIDE AND DIOXYGEN PHOTO-RELEASE, BINDING KINETICS, AND THERMODYNAMICS IN 1:1 MONONUCLEAR AND 2:1 DINUCLEAR COPPER/DIOXYGEN COMPLEXES. [Thesis]. Johns Hopkins University; 2014. Available from: http://jhir.library.jhu.edu/handle/1774.2/37054

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Open Access Theses and Dissertations