You searched for subject:(Asymmetric catalysis).
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University of Edinburgh
1.
Bao, Wei.
Exploration of the catalytic use of alkali metal bases.
Degree: PhD, 2017, University of Edinburgh
URL: http://hdl.handle.net/1842/28799 
► This PhD thesis project was concerned with the use of alkali metal amide Brønsted bases and alkali metal alkoxide Lewis bases in (asymmetric) catalysis. The…
(more)
▼ This PhD thesis project was concerned with the use of alkali metal amide Brønsted bases and alkali metal alkoxide Lewis bases in (asymmetric) catalysis. The first chapter deals with formal allylic C(sp3)–H bond activation of aromatic and functionalized alkenes for subsequent C–C and C–H bond formations. The second chapter is focused on C(sp3)–Si bond activation of fluorinated pro-nucleophiles in view of C–C bond formations. In the first chapter, a screening of various metal amides, hydrides, and alkyl reagents resulted in the observation that alkali metal amides were effective Brønsted bases to trigger allylic C(sp3)–H bond activation of aromatic alkenes at room temperature. Sodium hexamethyldisilazide was found to be most efficient compared with other s-, p-, d-, and fblock metal amides. This unique transition metal-free methodology was exploited to activate a variety of alkene pro-nucleophiles, which were shown to undergo γ-selective C–C bond formation with various aromatic aldimines as well as one aliphatic substrate. The corresponding homoallylic amine derivatives were obtained in high yields with excellent E:Z ratios. The reaction mechanism was investigated and attempts to detect and/or isolate key intermediates were undertaken. Importantly, it was shown that metal-free superbases of the Schwesinger or Verkade type were not apt to catalyse this challenging C–C bond formation. The asymmetric version of this rare sodium amide catalysis has been achieved by using a commercially available enantiopure bisoxazoline ligand (46% ee). Subsequently, the catalytic use of sodium and potassium amides was applied to the isomerization of terminal aromatic alkenes to generate the thermodynamically more stable internal olefins in excellent yields with high E:Z ratios. Furthermore, functionalized metalloid (B, Si) and metal-free alkenes were found to undergo alkali metal amide-triggered (chemoselective) allylic C(sp3)–H bond activation in view of isomerization and/or C–C bond formation with aldimines. In the second chapter, the catalytic C–Si bond activation of an important difluoromethylation reagent, HCF2SiMe3, was investigated. Here, alkali metal alkoxides were shown to be more effective Lewis base triggers than other metal alkoxides or metal-free superbases. This novel method was successfully used to transfer the nucleophilic difluoromethyl fragment to electrophiles such as a variety of amides and lactams, whereas unsaturated amides failed to undergo the intended conjugate C–C bond formation. In this context, it is noted that the α-hydrogen of certain amides was tolerated. This unprecedented catalytic difluoromethylation of unactivated carbonyl electrophiles was achieved using potassium tert-butoxide at room temperature, and the corresponding fluorinated ‘hemiaminal’ products were obtained in high yields.
Subjects/Keywords: catalysis; asymmetric catalysis; Brønsted bases
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APA (6th Edition):
Bao, W. (2017). Exploration of the catalytic use of alkali metal bases. (Doctoral Dissertation). University of Edinburgh. Retrieved from http://hdl.handle.net/1842/28799
Chicago Manual of Style (16th Edition):
Bao, Wei. “Exploration of the catalytic use of alkali metal bases.” 2017. Doctoral Dissertation, University of Edinburgh. Accessed October 18, 2019.
http://hdl.handle.net/1842/28799.
MLA Handbook (7th Edition):
Bao, Wei. “Exploration of the catalytic use of alkali metal bases.” 2017. Web. 18 Oct 2019.
Vancouver:
Bao W. Exploration of the catalytic use of alkali metal bases. [Internet] [Doctoral dissertation]. University of Edinburgh; 2017. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/1842/28799.
Council of Science Editors:
Bao W. Exploration of the catalytic use of alkali metal bases. [Doctoral Dissertation]. University of Edinburgh; 2017. Available from: http://hdl.handle.net/1842/28799
University of Oxford
2.
Maciver, Eleanor E.
Asymmetric electrocyclic reactions.
Degree: PhD, 2013, University of Oxford
URL: http://ora.ox.ac.uk/objects/uuid:17ba3cb0-0c62-406a-bed4-14c410a45918
;
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.588436
► Pericyclic reactions are a class of transformations that comprise sigmatropic rearrangements, group transfer reactions, cycloadditions and electrocyclic reactions. Since Woodward and Hoffmann rationalized the mechanism…
(more)
▼ Pericyclic reactions are a class of transformations that comprise sigmatropic rearrangements, group transfer reactions, cycloadditions and electrocyclic reactions. Since Woodward and Hoffmann rationalized the mechanism and stereochemistry of pericyclic reactions they have become powerful synthetic tools. Whilst sigmatropic rearrangements and cycloadditions are cornerstones of contemporary synthetic methodology, many electrocyclic reactions are not fully exploited currently; there are no general methods for the asymmetric catalysis of electrocyclic reactions and as a consequence, opportunities for exerting stereocontrol in these manifolds are limited. We aim to establish general methods for the asymmetric catalysis of 6π electrocyclic reactions. Our initial studies are focused on a pentadienyl anion moiety due to the greater ease of cyclization observed with such systems in comparison to the corresponding neutral hexatriene systems.
Subjects/Keywords: 547; Asymmetric catalysis; Electrocyclization; Asymmetric; Catalysis
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APA (6th Edition):
Maciver, E. E. (2013). Asymmetric electrocyclic reactions. (Doctoral Dissertation). University of Oxford. Retrieved from http://ora.ox.ac.uk/objects/uuid:17ba3cb0-0c62-406a-bed4-14c410a45918 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.588436
Chicago Manual of Style (16th Edition):
Maciver, Eleanor E. “Asymmetric electrocyclic reactions.” 2013. Doctoral Dissertation, University of Oxford. Accessed October 18, 2019.
http://ora.ox.ac.uk/objects/uuid:17ba3cb0-0c62-406a-bed4-14c410a45918 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.588436.
MLA Handbook (7th Edition):
Maciver, Eleanor E. “Asymmetric electrocyclic reactions.” 2013. Web. 18 Oct 2019.
Vancouver:
Maciver EE. Asymmetric electrocyclic reactions. [Internet] [Doctoral dissertation]. University of Oxford; 2013. [cited 2019 Oct 18].
Available from: http://ora.ox.ac.uk/objects/uuid:17ba3cb0-0c62-406a-bed4-14c410a45918 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.588436.
Council of Science Editors:
Maciver EE. Asymmetric electrocyclic reactions. [Doctoral Dissertation]. University of Oxford; 2013. Available from: http://ora.ox.ac.uk/objects/uuid:17ba3cb0-0c62-406a-bed4-14c410a45918 ; https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.588436
Brock University
3.
Zaifman, Joshua David.
Stereoselective synthesis of substituted hexahydro-3a,4a-diazacyclopentaphenanthren-4-ones and aminoferrocenes
.
Degree: Department of Chemistry, 2011, Brock University
URL: http://hdl.handle.net/10464/3383
► This thesis explored the development of several methodologies for the stereoselective construction of ligand frameworks and some of their applications. The first segment concerns the…
(more)
▼ This thesis explored the development of several methodologies for the
stereoselective construction of ligand frameworks and some of their applications. The
first segment concerns the application of an enantioselective lithiation at an Sp3_
hybridized position adjacent to nitrogen by means of the widely used and typically highly
effective enantioselective lithiation with ( -)-sparteine. This investigation was intended to
develop a method to install chirality into a system that would be converted into a family
of diaminoylidenes for use as phosphine mimics in transition metal catalysis or as
nucleophilic reagents. Molecular modeling of the system revealed some key interactions
between the substrate and (-)-sparteine that provided general insight into the diamine's
mode of action and should lend some predictive value to its future applications.
The second portion focuses on the development of methods to access 1,2-
disubstituted aminoferrocenes, an underexplored class of metallocenes possessing planar
chirality. Two routes were examined involving a diastereoselective and an
enantioselective pathway, where the latter method made use of the first BF3-mediated
lithiation-substitution to install planar chirality. Key derivatives such as 1,2-
aminophosphines, made readily accessible by the new route, were evaluated as ligands
for Pd(II), Pt(II) and Ir(I). These complexes show activity in a number of transformations
with both achiral and prochiral substrates. Optimization experiments were conducted to
prepare enantiomerically enriched 2-substituted-I-aminoferrocenes by direct asymmetric
lithiation of BF3-coordinated tertiary aminoferrocenes. A predictive computational model
describing the transition state of this reaction was developed in collaboration with
Professor Travis Dudding's group (Department of Chemistry, Brock University). The predicted stereochemistry of the process was confirmed by single-crystal X-ray analysis
of a 2-phosphino-l-dimethylaminoferrocene derivative. Enantiomerically pure samples of
the aminophosphine ligands derived from this new process have given promising
preliminary results in the enantioselective hydrogenation of prochiral alkenes and warrant
further stUdy in metal-mediated catalysis.
Subjects/Keywords: Asymmetric synthesis;
Catalysis
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APA (6th Edition):
Zaifman, J. D. (2011). Stereoselective synthesis of substituted hexahydro-3a,4a-diazacyclopentaphenanthren-4-ones and aminoferrocenes
. (Thesis). Brock University. Retrieved from http://hdl.handle.net/10464/3383
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zaifman, Joshua David. “Stereoselective synthesis of substituted hexahydro-3a,4a-diazacyclopentaphenanthren-4-ones and aminoferrocenes
.” 2011. Thesis, Brock University. Accessed October 18, 2019.
http://hdl.handle.net/10464/3383.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zaifman, Joshua David. “Stereoselective synthesis of substituted hexahydro-3a,4a-diazacyclopentaphenanthren-4-ones and aminoferrocenes
.” 2011. Web. 18 Oct 2019.
Vancouver:
Zaifman JD. Stereoselective synthesis of substituted hexahydro-3a,4a-diazacyclopentaphenanthren-4-ones and aminoferrocenes
. [Internet] [Thesis]. Brock University; 2011. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10464/3383.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zaifman JD. Stereoselective synthesis of substituted hexahydro-3a,4a-diazacyclopentaphenanthren-4-ones and aminoferrocenes
. [Thesis]. Brock University; 2011. Available from: http://hdl.handle.net/10464/3383
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Notre Dame
4.
Eric C. Hansen.
Development and Applications of Quantum to Molecular
Mechanics (Q2MM)</h1>.
Degree: PhD, Chemistry and Biochemistry, 2017, University of Notre Dame
URL: https://curate.nd.edu/show/wd375t37h4h
► Asymmetric synthesis is a major focus in modern organic chemistry. Experimentally screening for selective ligands is a cumbersome process, and provides only indirect insight…
(more)
▼ Asymmetric synthesis is a major focus in
modern organic chemistry. Experimentally screening for selective
ligands is a cumbersome process, and provides only indirect insight
into the molecular origin of selectivity. Transition state force
fields generated by the Quantum to Molecular Mechanics (Q2MM)
method can describe the stereoselecting transition states involved
in reactions of interest to synthetic chemistry with the accuracy
of electronic structure methods but the speed of force field
calculations. This can provide structural and mechanistic
rationales for experimental observations and make quantitative
predictions before experimental ligand screening. This thesis
presents a robust code for performing Q2MM parameterization of
ground state and transition state force fields and improvements to
Q2MM. An automated virtual screening program is developed, which
works alongside Q2MM to rapidly perform virtual screens of ligands
in
asymmetric catalysis. The capabilities of Q2MM are demonstrated
in a study of the conformations of sulfones and sulfonamides, which
were investigated using high level electronic structure methods.
They revealed a dual anomeric effect, and the robustness of the
Q2MM method was demonstrated by parameterizing a force field that
implicitly captured these complicated electronic effects. Lastly,
the mechanism and structural origin of an unexpected
stereoselection observed in the rhodium catalyzed hydrogenation of
cyclic dehydrooligopeptides was studied using
Q2MM.
Advisors/Committee Members: Olaf Wiest, Research Director, Per-Ola Norrby, Committee Member, Jeffrey W. Peng, Committee Member, J. Daneil Gezelter, Committee Member.
Subjects/Keywords: Chemistry; Asymmetric catalysis
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APA (6th Edition):
Hansen, E. C. (2017). Development and Applications of Quantum to Molecular
Mechanics (Q2MM)</h1>. (Doctoral Dissertation). University of Notre Dame. Retrieved from https://curate.nd.edu/show/wd375t37h4h
Chicago Manual of Style (16th Edition):
Hansen, Eric C.. “Development and Applications of Quantum to Molecular
Mechanics (Q2MM)</h1>.” 2017. Doctoral Dissertation, University of Notre Dame. Accessed October 18, 2019.
https://curate.nd.edu/show/wd375t37h4h.
MLA Handbook (7th Edition):
Hansen, Eric C.. “Development and Applications of Quantum to Molecular
Mechanics (Q2MM)</h1>.” 2017. Web. 18 Oct 2019.
Vancouver:
Hansen EC. Development and Applications of Quantum to Molecular
Mechanics (Q2MM)</h1>. [Internet] [Doctoral dissertation]. University of Notre Dame; 2017. [cited 2019 Oct 18].
Available from: https://curate.nd.edu/show/wd375t37h4h.
Council of Science Editors:
Hansen EC. Development and Applications of Quantum to Molecular
Mechanics (Q2MM)</h1>. [Doctoral Dissertation]. University of Notre Dame; 2017. Available from: https://curate.nd.edu/show/wd375t37h4h
Rutgers University
5.
Nguyen, Hiep Nhu, 1983-.
Binaphtholate and octahydrobinaphtholate rare-earth metal catalysts for asymmetric hydroamination of alkenes.
Degree: PhD, Chemistry and Chemical Biology, 2018, Rutgers University
URL: https://rucore.libraries.rutgers.edu/rutgers-lib/59179/
► In this thesis we summarize our efforts towards the development of binaphtholate and octahydrobinaptholate rare-earth metal complexes for asymmetric hydroamination of aminoalkenes, as well as…
(more)
▼ In this thesis we summarize our efforts towards the development of binaphtholate and octahydrobinaptholate rare-earth metal complexes for
asymmetric hydroamination of aminoalkenes, as well as kinetic resolution of chiral aminoalkenes via hydroamination. These complexes were also found to be efficient catalysts for the
asymmetric intermolecular hydroamination of unactivated alkenes with simple amines. Catalytic screening results indicated that increasing steric bulk of the silyl-substituents in the ligand and decreasing ionic radius of the rare earth metal helped increase catalytic activity and enantioselectivity of the hydroamination product. Consistent with our previous findings, the hydroamination reaction catalyzed by these complexes showed zero order rate dependence on substrate concentration and first order rate dependence on catalyst concentration. In most cases, octahydrobinaphtholate complexes (R)-[Ln{L}(o-C6H4- CH2NMe2)(Me2NCH2Ph)] (Ln = Y, Lu; L = 3,3’-bis(triphenylsilyl)-5,5’,6,6’,7,7’, 8,8’-octahydro-1,1’-binaphthyl-2,2’-diolate (50a-Ln); L = 3,3’-bis(tert-butyldiphenyl silyl)-5,5’,6,6’,7,7’,8,8’-octahydro-1,1’-binaphthyl-2,2’-diolate (50b-Ln); and L = 3,3’-bis(cyclohexyldiphenylsilyl)-5,5’,6,6’,7,7’,8,8’-octahydro-1,1’-binaphthyl-2,2’-diolate (50c-Ln)) were shown to be more reactive and more enantioselective catalysts for
asymmetric hydroamination than their related binaphtholate complexes (R)-[Ln{L}(o-C6H4CH2NMe2)(Me2NCH2Ph)] (Ln = Y, Lu; L = 3,3’-bis(triphenylsilyl)-1,1’-binaphthyl-2,2’-diolate (19a-Ln); L = 3,3’-bis(tert-butyldiphenylsilyl)-1,1’-binaphthyl-2,2’-diolate (39b-Ln); and L = 3,3’-bis(cyclohexyldiphenylsilyl)-1,1’-binaphthyl-2,2’-diolate (39c-Ln)). Turnover frequencies as high as 2400 h−1 were achieved for 2,2-diphenyl-pent-4-enylamine using (R)-50c-Y and enantiomeric excess of up to 98% could be obtained in the cyclization of C-(1-allylcyclohexyl)-methylamine using (R)-50c-Lu at room temperature. The stability of binaphtholate and octahydrobinaphtholate rare earth metal catalysts at elevated temperature of up to 150 C extended their usages for
asymmetric intermolecular hydroamination of simple amines and unactivated alkenes, forming exclusively Markovnikov amine products. (R)-50a-Y displayed the high efficiency for catalytic addition of benzylamine to 4-phenyl-1-butene at 110 C, affording (R)-N-benzyl-4-phenylbutan-2-amine, with enantiomeric excess of up to 67%. The complexes were also suitable for kinetic resolution of chiral alpha-substituted aminoalkenes via catalytic
asymmetric hydroamination. Kinetic resolution factors f of up to 90 and equilibrium constant Kdias of up to 5.1, indicating a Curtin-Hammett pre-equilibrium favoring the matching combination of substrate and complex, were observed for 1-methylpent-4-enylamine using (R)-39c-Y at 25 C. The 2,5-disubstituted pyrrolidines were formed in 7:1 to ≥ 50:1 trans diastereoselectivity, depending on the size of the alpha-substituent of the aminoalkene. Kinetic studies of (S)-1-methylpent-4-enylamine provided an access to activation…
Advisors/Committee Members: Goldman, Alan (chair), School of Graduate Studies.
Subjects/Keywords: Asymmetric hydroamination; Catalysis
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APA (6th Edition):
Nguyen, Hiep Nhu, 1. (2018). Binaphtholate and octahydrobinaphtholate rare-earth metal catalysts for asymmetric hydroamination of alkenes. (Doctoral Dissertation). Rutgers University. Retrieved from https://rucore.libraries.rutgers.edu/rutgers-lib/59179/
Chicago Manual of Style (16th Edition):
Nguyen, Hiep Nhu, 1983-. “Binaphtholate and octahydrobinaphtholate rare-earth metal catalysts for asymmetric hydroamination of alkenes.” 2018. Doctoral Dissertation, Rutgers University. Accessed October 18, 2019.
https://rucore.libraries.rutgers.edu/rutgers-lib/59179/.
MLA Handbook (7th Edition):
Nguyen, Hiep Nhu, 1983-. “Binaphtholate and octahydrobinaphtholate rare-earth metal catalysts for asymmetric hydroamination of alkenes.” 2018. Web. 18 Oct 2019.
Vancouver:
Nguyen, Hiep Nhu 1. Binaphtholate and octahydrobinaphtholate rare-earth metal catalysts for asymmetric hydroamination of alkenes. [Internet] [Doctoral dissertation]. Rutgers University; 2018. [cited 2019 Oct 18].
Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/59179/.
Council of Science Editors:
Nguyen, Hiep Nhu 1. Binaphtholate and octahydrobinaphtholate rare-earth metal catalysts for asymmetric hydroamination of alkenes. [Doctoral Dissertation]. Rutgers University; 2018. Available from: https://rucore.libraries.rutgers.edu/rutgers-lib/59179/
Baylor University
6.
Bell, Jason R.
Synthesis and application of C₂ asymmetric phosphinines via their pyrylium salt precursors.
Degree: Chemistry and Biochemistry., 2010, Baylor University
URL: http://hdl.handle.net/2104/7925
► The development of new chiral ligands for asymmetric catalysis is an increasingly important area of research. Though many ligands are phosphorus based, one class of…
(more)
▼ The development of new chiral ligands for
asymmetric catalysis is an increasingly important area of research. Though many ligands are phosphorus based, one class of phosphorus ligands, phosphinines (phosphabenzenes), have been little studied. Most studies of chiral phosphinines, especially for those used in
asymmetric catalysis have involved essentially attaching achiral phosphinines to chiral auxiliaries. The synthesis of the first C₂ chiral phosphinine was accomplished by converting (+)-camphor to the corresponding pyrylium salt, and then converting the pyrylium to the phosphinine. Though several initial attempts failed at forming the necessary pyrylium salt using simpler synthetic methods, an effective route for forming the pyrylium was chosen utilizing the preformed 3-ene-1,5-dione precursor. The camphor-based phosphinine was fully characterized and applied to two
asymmetric catalytic test reactions,
asymmetric hydrosilylation and
asymmetric hydrogenation. Though (+)-camphor provided a convenient, cost-effective, and enantiomerically pure starting material, nature provides few compounds fitting all the necessary requirements for the starting materials. Therefore, derivatized cyclohexanones were also synthesized. Specifically, pyryliums salts based on 2-methyl-2-phenylcyclohexanone were synthesized, albeit in low yield. Attempts to use the improved synthetic method developed for the camphor-based pyryliums failed at the chlorination stage. Attempts to convert the (+)-camphor chlorobenzylidene intermediate into C₁ chiral pyryliums also failed. The C₂
asymmetric phosphinine based on camphor did react with benzyne to yield a new chiral phosphabarrelene.
Advisors/Committee Members: Garner, Charles M. (Charles Manley), 1957- (advisor).
Subjects/Keywords: Organic chemistry.;
Asymmetric catalysis.;
Phosphinines.
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APA ·
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APA (6th Edition):
Bell, J. R. (2010). Synthesis and application of C₂ asymmetric phosphinines via their pyrylium salt precursors.
(Thesis). Baylor University. Retrieved from http://hdl.handle.net/2104/7925
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Bell, Jason R. “Synthesis and application of C₂ asymmetric phosphinines via their pyrylium salt precursors.
” 2010. Thesis, Baylor University. Accessed October 18, 2019.
http://hdl.handle.net/2104/7925.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Bell, Jason R. “Synthesis and application of C₂ asymmetric phosphinines via their pyrylium salt precursors.
” 2010. Web. 18 Oct 2019.
Vancouver:
Bell JR. Synthesis and application of C₂ asymmetric phosphinines via their pyrylium salt precursors.
[Internet] [Thesis]. Baylor University; 2010. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/2104/7925.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Bell JR. Synthesis and application of C₂ asymmetric phosphinines via their pyrylium salt precursors.
[Thesis]. Baylor University; 2010. Available from: http://hdl.handle.net/2104/7925
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Penn State University
7.
Zhang, Weicheng.
DEVELOPMENT OF EFFECTIVE CHIRAL LIGANDS FOR CATALYTIC
ASYMMETRIC HYDROGENATION.
Degree: PhD, Chemistry, 2009, Penn State University
URL: https://etda.libraries.psu.edu/catalog/9308
► This thesis summarizes the author’s graduate research on catalytic asymmetric hydrogenation at Penn State. The first chapter gives a brief review of ligand development in…
(more)
▼ This thesis summarizes the author’s graduate research
on catalytic asymmetric hydrogenation at Penn State. The first
chapter gives a brief review of ligand development in asymmetric
hydrogenation, with a focus on the long-term effort of the Zhang
group in this area. Several important factors for ligand design are
discussed, including steric hindrance, electronic control, and
practical considerations. Chapter 2 delineates the development of a
novel triphosphorus bidentate phosphine-phosphoramidite ligand with
pseudo C2-symmetry, from initial design, through ligand synthesis
and characterization, to its application in asymmetric
hydrogenation. A major success of this ligand is highlighted in
asymmetric hydrogenation of ortho substituted á-arylenamides with
excellent enantioselectivity (up to 99.6% ee), which had not been
possible prior to this work. In Chapter 3, the development of
conformationally rigid spirocyclic monodentate phosphoramidite
ligands is discussed. A highly efficient, large-scale route for the
synthesis of chiral spirocyclic diol is presented, followed by the
discovery of an interesting acid-mediated rearrangement of
spirocyclic backbones. These spirocyclic ligands are applied in
highly enantioselective catalytic asymmetric hydrogenation and
asymmetric conjugate addition reactions.
Subjects/Keywords: hydrogenation; asymmetric; catalysis; ligand;
rhodium
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APA ·
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Manager
APA (6th Edition):
Zhang, W. (2009). DEVELOPMENT OF EFFECTIVE CHIRAL LIGANDS FOR CATALYTIC
ASYMMETRIC HYDROGENATION. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/9308
Chicago Manual of Style (16th Edition):
Zhang, Weicheng. “DEVELOPMENT OF EFFECTIVE CHIRAL LIGANDS FOR CATALYTIC
ASYMMETRIC HYDROGENATION.” 2009. Doctoral Dissertation, Penn State University. Accessed October 18, 2019.
https://etda.libraries.psu.edu/catalog/9308.
MLA Handbook (7th Edition):
Zhang, Weicheng. “DEVELOPMENT OF EFFECTIVE CHIRAL LIGANDS FOR CATALYTIC
ASYMMETRIC HYDROGENATION.” 2009. Web. 18 Oct 2019.
Vancouver:
Zhang W. DEVELOPMENT OF EFFECTIVE CHIRAL LIGANDS FOR CATALYTIC
ASYMMETRIC HYDROGENATION. [Internet] [Doctoral dissertation]. Penn State University; 2009. [cited 2019 Oct 18].
Available from: https://etda.libraries.psu.edu/catalog/9308.
Council of Science Editors:
Zhang W. DEVELOPMENT OF EFFECTIVE CHIRAL LIGANDS FOR CATALYTIC
ASYMMETRIC HYDROGENATION. [Doctoral Dissertation]. Penn State University; 2009. Available from: https://etda.libraries.psu.edu/catalog/9308
University of California – Berkeley
8.
Brown, Casey Jameson.
Asymmetric and Organometallic Catalysis Mediated by a Chiral Supramolecular Host.
Degree: Chemistry, 2011, University of California – Berkeley
URL: http://www.escholarship.org/uc/item/7jv7m4wh
► Chapter 1. An overview of supramolecular catalysis is presented with attention to the diverse strategies used in developing these materials. Different strategies for the design…
(more)
▼ Chapter 1. An overview of supramolecular catalysis is presented with attention to the diverse strategies used in developing these materials. Different strategies for the design and preparation of chiral supramolecular structures are described along with their applications to enantioselective binding and catalysis. The intrinsically chiral M4L612- supramolecular assembly developed by the Raymond group is introduced, and its catalytic scope is reviewed.Chapter 2. The development of an asymmetric variant of the aza-Cope transformation is presented. Application of the resolved Ga4L612- assembly to this catalytic transformation gives modest but significant enantioselectivity (up to 64% ee) with a varied scope of allyl enammonium cations. This represents the first reported example of asymmetric supramolecular catalysis with substantial enantioselectivity and catalytic turnover. Use of a relatively unreactive substrate allowed characterization of a host-substrate complex by X-ray diffraction, giving insight into the means of enantiodifferentiation by the chiral host. Additionally, the structure of the M4L612- assembly was modified by substituting other trivalent cations (Fe3+, 3+) into the M4L612- host, modulating the enantioselectivity of the rearrangement. Efforts to emulate allosteric regulation using externally associated chiral cations are also described.Chapter 3. The engineering of a high-turnover supramolecular catalyst containing a cationic ruthenium complex is described. The RuCp(PMe3)(MeCN)2+ cation, an allyl alcohol isomerization catalyst, was incorporated into the Ga4L612- assembly. While encapsulated, the organometallic complex experiences only mild rate attenuations, while maintaining its remarkably high activity. This hybrid catalyst is capable of more than 1000 turnovers, eclipsing other known supramolecular catalysts. The kinetics of catalysis are also analyzed, revealing inhibition both by acetonitrile and the allyl alcohol substrates. The protection offered by encapsulation in the assembly also allowed the preparation of the larger RuCp*(PMe3)(MeCN)2+ complex, which is both stable and catalytically active. Preliminary investigations of this complex are described.Chapter 4. Cationic gold(I) catalysts encapsulated inside assembly 1</bold are applied as supramolecular catalysts. In the presence of the Ga4L6 assembly, R3PAuX (X = Cl, Br) complexes have been found to lose their halide ligand and reside in the nanovessel's cavity as the free cation. This host-guest complex is catalytically active in both the hydroalkoxylation and hydroamination of allenes, generating cyclic, chiral ethers and amines. The rate of catalysis for the bound gold cation is observed to be higher than that for the…
Subjects/Keywords: Chemistry; asymmetric; catalysis; organometallic; supramolecular
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APA (6th Edition):
Brown, C. J. (2011). Asymmetric and Organometallic Catalysis Mediated by a Chiral Supramolecular Host. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/7jv7m4wh
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Brown, Casey Jameson. “Asymmetric and Organometallic Catalysis Mediated by a Chiral Supramolecular Host.” 2011. Thesis, University of California – Berkeley. Accessed October 18, 2019.
http://www.escholarship.org/uc/item/7jv7m4wh.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Brown, Casey Jameson. “Asymmetric and Organometallic Catalysis Mediated by a Chiral Supramolecular Host.” 2011. Web. 18 Oct 2019.
Vancouver:
Brown CJ. Asymmetric and Organometallic Catalysis Mediated by a Chiral Supramolecular Host. [Internet] [Thesis]. University of California – Berkeley; 2011. [cited 2019 Oct 18].
Available from: http://www.escholarship.org/uc/item/7jv7m4wh.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Brown CJ. Asymmetric and Organometallic Catalysis Mediated by a Chiral Supramolecular Host. [Thesis]. University of California – Berkeley; 2011. Available from: http://www.escholarship.org/uc/item/7jv7m4wh
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Illinois – Urbana-Champaign
9.
Liu, Wei.
Asymmetric allylic C–H functionalization via palladium(II)/sulfoxide-oxazoline catalysis.
Degree: PhD, Chemistry, 2018, University of Illinois – Urbana-Champaign
URL: http://hdl.handle.net/2142/102431
► Asymmetric C–H functionalization could deliver a highly efficient transformation by installing both oxidized functionality and absolute stereochemistry simultaneously. In this context, palladium(II)-catalyzed asymmetric allylic C–H…
(more)
▼ Asymmetric C–H functionalization could deliver a highly efficient transformation by installing both oxidized functionality and absolute stereochemistry simultaneously. In this context, palladium(II)-catalyzed
asymmetric allylic C–H functionalization of terminal olefins through the intermediacy of π-allyl/Pd(II) complex represents a viable platform. Traditionally, the
asymmetric functionalization of π-allyl/Pd(II) intermediate generally proceeded with phosphine-based ligands, under redox-neutral and basic conditions. Current efforts to develop the oxidative allylic C–H functionalization reaction have focused on the adaptation of phosphine-based ligands, which are prone to oxidation. As such, these systems suffer from limited substrate scope (activated olefins, e.g. allylarenes) and modest enantioselectivity. Alternatively, the oxidatively stable bis-sulfoxide ligand has shown to promote general reactivity with broad scope. However, its underlying mechanism, known as “serial ligand catalysis”, is challenging for
asymmetric catalysis, due to the highly dynamic and fluxional binding environment of palladium. This work describes the development of oxidatively stable, chiral sulfoxide-oxazoline ligands for palladium(II)-catalyzed
asymmetric allylic C–H oxidations and alkylations. The design principle is to combine the sulfoxide moiety, known to promote C–H cleavage, with a strongly coordinately oxazoline moiety that can anchor the ligand to the metal and thereby provide a stable chiral environment. Additionally, the σ-donation from oxazoline could promote the formation of a cationic π-allyl/Pd(II) intermediate, which becomes more reactive towards functionalization.
The first chapter of this dissertation describes the development of a general intermolecular allylic C–H alkylation with tertiary nucleophiles under palladium(II)/bis-sulfoxide
catalysis. This work laid the foundation for
asymmetric processes with the resultant quaternary stereogenic centers that would not be prone to racemization. This reaction incorporates a broad scope of terminal olefins (e.g. aromatic, aliphatic) and tertiary nucleophiles (e.g. nitroketones, β-ketoesters) with good yields and excellent selectivities (>20:1 linear:branched, >20:1 E:Z). The use of tertiary nucleophiles allows for strategic incorporation of latent functionality into the alkylation partner, which can be exploited for further elaboration to generate molecular complexity. This concept is demonstrated in a tandem allylic C–H alkylation/Diels-Alder reaction sequence: a reactive diene is generated upon the alkylation of a terminal olefin and trapped by a dienophile contained within the tertiary nucleophile to afford a complex tricyclic core structure.
The second chapter describes the development of chiral sulfoxide-oxazoline (SOX) ligands for Pd(II)-catalyzed enantioselective allylic C–H oxidation. Chiral isochromans are formed by the intramolecular cyclization between alcohol and terminal olefin, leading to good yields and high enantioselectivities (>90% ee). Pd(II)/trans-SOX…
Advisors/Committee Members: White, Maria Christina (advisor), White, Maria Christina (Committee Chair), Denmark, Scott E (committee member), Hergenrother, Paul J (committee member), Fout, Alison R (committee member).
Subjects/Keywords: C–H Activation; Asymmetric Catalysis
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APA (6th Edition):
Liu, W. (2018). Asymmetric allylic C–H functionalization via palladium(II)/sulfoxide-oxazoline catalysis. (Doctoral Dissertation). University of Illinois – Urbana-Champaign. Retrieved from http://hdl.handle.net/2142/102431
Chicago Manual of Style (16th Edition):
Liu, Wei. “Asymmetric allylic C–H functionalization via palladium(II)/sulfoxide-oxazoline catalysis.” 2018. Doctoral Dissertation, University of Illinois – Urbana-Champaign. Accessed October 18, 2019.
http://hdl.handle.net/2142/102431.
MLA Handbook (7th Edition):
Liu, Wei. “Asymmetric allylic C–H functionalization via palladium(II)/sulfoxide-oxazoline catalysis.” 2018. Web. 18 Oct 2019.
Vancouver:
Liu W. Asymmetric allylic C–H functionalization via palladium(II)/sulfoxide-oxazoline catalysis. [Internet] [Doctoral dissertation]. University of Illinois – Urbana-Champaign; 2018. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/2142/102431.
Council of Science Editors:
Liu W. Asymmetric allylic C–H functionalization via palladium(II)/sulfoxide-oxazoline catalysis. [Doctoral Dissertation]. University of Illinois – Urbana-Champaign; 2018. Available from: http://hdl.handle.net/2142/102431
Texas A&M University
10.
Ghosh, Subrata Kumar.
The Development of New Classes of Enantioselective Hydrogen Bond Donor Catalysts for Organic Synthesis Based upon Werner Complexes.
Degree: PhD, Chemistry, 2017, Texas A&M University
URL: http://hdl.handle.net/1969.1/169551
► In this dissertation, the development of highly effective, chiral monofunctional and bifunctional hydrogen bond donor catalysts based on cobalt(III) Werner complexes and their applications in…
(more)
▼ In this dissertation, the development of highly effective, chiral monofunctional and
bifunctional hydrogen bond donor catalysts based on cobalt(III) Werner complexes and
their applications in enantioselective
catalysis have been described. Furthermore, a
protocol was developed to extend this chemistry into the fluorous media.
Section 1 provides an overview of the hydrogen bond mediated organocatalysis
and the scope of Werner complexes as hydrogen bond donors.
Section 2 describes the fundamental stereochemical features of the trication
[Co(en)3]3+ (en = ethylenediamine). Interactions between the trication, counter anions,
and solvates are analyzed and a systematic nomenclature is developed.
Section 3 provides highly diastereoselective syntheses of variety of diastereopure
salts Λ- and Δ-[Co((S,S)-NHv2CHArCHArNHv2)v3]
3+ 2X–X'– (Ar = Cv6Hv5, vCv6Hv4n-Bu, 4-
Cv6Hv4Cl, 4-Cv6Hv4CFv3, 4-Cv6Hv4OCHv3, ɑ-naphthyl, ß-naphthyl, 2-Cv6Hv4OBn; X/X' =
Cl/BArvf (BArvf = B(3,5-Cv6Hv3(CFv3)v2)v4), PFv6/BArf, BF4/BArf, PhBF3/BArf, Cl/BArf20
(BArvf20 = B(Cv6F5)4), BArf/BArf, BArf20/BArvf20, BFv4/BFv4, PFv6/PFv6) and probes their
properties.
Sections 4 and 5 provide detail applications of the lipophilic salts of Λ- or Δ-
[Co((S,S)-dpen)v3]
3+ ((S,S)-dpen = (S,S)-1,2-diphenylethylenediamine) in enantioselective
addition reactions. Under optimized conditions, Λ-[Co((S,S)-dpen)v3]
3+ 3BFv4–
catalyzes the Michael addition of dialkyl malonate to nitroalkenes in the presence of
Et3N, affording adducts in up to 98% yields and 96% ee. Interestingly, Δ-[Co((S,S)-
dpen)v3]
3+ 2Cl–BArvf20– is superior for the additions of cyclic ß-ketoesters to
azodicarboylate diesters (up to 99% yields and >99% ee).
Section 6 describes efficient syntheses of tris(hydrochloric acid) salts of chiral
triamines Hv2NCH((CHv2)nNMe2)CHv2NHv2 (n = 1-4) from commercial starting materials
in overall yields of 38-18%.
Section 7 highlights syntheses of bifunctional catalysts and their applications in
additions of dialkyl malonates to nitroalkenes. Racemic [Co(en)v2Ov2CO]
+ Cl^– and
enantiopure (S)-[Hv3NCH((CH2)nNHMe2)CHv2NHv3]
3+ 3Cl^– (n = 1-4) are combined (water/
charcoal/100 °C) to give [Co(en)v2((S)-Hv2NCH((CHv2)vnNMev2H)CHv2NHv2)]4
+ 4Cl^–.
The cobalt diastereomers (Δ/Δ)are separated via chiral Sephadex columns. Reactions
with NaOH and Na
+ BArvf^– give the catalysts Λ- or Δ-[Co(en)v2((S)-Hv2NCH-
((CHv2)nNMev2)CHv2NHv2)]
3+ 3BArvf^–. Under optimized condition, Λ-[Co(en)v2((S)-
Hv2NCH((CHv2)v3NMev2)CHv2NHv2)]
3+ 3BArvf^– gives addition products up to 98% yield and
99% ee.
Section 8 describes an optimized procedure for the synthesis of highly fluorous
Na
+ B(3,5-Cv6Hv3((CFv2)5CFv3)v2)v4– and its application in transporting polycations into
fluorous media.
Advisors/Committee Members: Gladysz, John A (advisor), Singleton, Daniel A (committee member), Darensbourg, Donald J (committee member), Tarone, Aaron M (committee member).
Subjects/Keywords: Chiral; asymmetric; catalysis; cobalt; fluorous
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APA ·
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APA (6th Edition):
Ghosh, S. K. (2017). The Development of New Classes of Enantioselective Hydrogen Bond Donor Catalysts for Organic Synthesis Based upon Werner Complexes. (Doctoral Dissertation). Texas A&M University. Retrieved from http://hdl.handle.net/1969.1/169551
Chicago Manual of Style (16th Edition):
Ghosh, Subrata Kumar. “The Development of New Classes of Enantioselective Hydrogen Bond Donor Catalysts for Organic Synthesis Based upon Werner Complexes.” 2017. Doctoral Dissertation, Texas A&M University. Accessed October 18, 2019.
http://hdl.handle.net/1969.1/169551.
MLA Handbook (7th Edition):
Ghosh, Subrata Kumar. “The Development of New Classes of Enantioselective Hydrogen Bond Donor Catalysts for Organic Synthesis Based upon Werner Complexes.” 2017. Web. 18 Oct 2019.
Vancouver:
Ghosh SK. The Development of New Classes of Enantioselective Hydrogen Bond Donor Catalysts for Organic Synthesis Based upon Werner Complexes. [Internet] [Doctoral dissertation]. Texas A&M University; 2017. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/1969.1/169551.
Council of Science Editors:
Ghosh SK. The Development of New Classes of Enantioselective Hydrogen Bond Donor Catalysts for Organic Synthesis Based upon Werner Complexes. [Doctoral Dissertation]. Texas A&M University; 2017. Available from: http://hdl.handle.net/1969.1/169551
Rice University
11.
Sambasivan, Ramya.
Rh(II) metallopeptides for asymmetric catalysis.
Degree: PhD, Natural Sciences, 2015, Rice University
URL: http://hdl.handle.net/1911/95526
► The development of peptides as chiral ligands for asymmetric Rh(II) catalysis is discussed in this work. Mother Nature’s solution to chiral ligand design is to…
(more)
▼ The development of peptides as chiral ligands for
asymmetric Rh(II)
catalysis is discussed in this work. Mother Nature’s solution to chiral ligand design is to make use of the naturally available chiral building blocks – amino acids. Polypeptides, built from amino acids, provide a diverse, modular and functional-group-rich framework for the development of selective transition- metal catalysts and enable facile ligand screening.
The dirhodium core has a paddlewheel structure that can ligate readily to the side chain carboxylate of aspartate or glutamate in a peptide chain. When a peptide containing aspartates or glutamates in the i and i+4 position is complexed to dirhodium, the transition metal complex thus formed has a defined peptide secondary structure with retention of catalytic activity at the metal center.
The first-generation approach used a solution-phase library of dirhodium bis-peptide catalysts for the enantioselective Si–H bond insertion and cyclopropanation. The parallel and anti-parallel orientation of bis-peptide catalysts was determined by pyrene fluorescence. Subsequently, parallel on-bead screening of catalyst libraries allowed significantly higher throughput by obviating the need for purification and isolation of individual catalysts. This enables the synthesis and screening of catalysts in 96-well plate format within a few days. More recently, a mono-peptide catalyst with a tridentate eq-eq-ax peptide ligand has been identified which exhibits differential behavior in solution and on bead. New insights into the development of immobilized homogeneous catalysts for stereoselective
catalysis are discussed.
Advisors/Committee Members: Ball, Zachary T. (advisor), Engel, Paul S. (advisor), Verduzco, Rafael (committee member).
Subjects/Keywords: metallopeptide; asymmetric catalysis; rhodium catalyst
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APA (6th Edition):
Sambasivan, R. (2015). Rh(II) metallopeptides for asymmetric catalysis. (Doctoral Dissertation). Rice University. Retrieved from http://hdl.handle.net/1911/95526
Chicago Manual of Style (16th Edition):
Sambasivan, Ramya. “Rh(II) metallopeptides for asymmetric catalysis.” 2015. Doctoral Dissertation, Rice University. Accessed October 18, 2019.
http://hdl.handle.net/1911/95526.
MLA Handbook (7th Edition):
Sambasivan, Ramya. “Rh(II) metallopeptides for asymmetric catalysis.” 2015. Web. 18 Oct 2019.
Vancouver:
Sambasivan R. Rh(II) metallopeptides for asymmetric catalysis. [Internet] [Doctoral dissertation]. Rice University; 2015. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/1911/95526.
Council of Science Editors:
Sambasivan R. Rh(II) metallopeptides for asymmetric catalysis. [Doctoral Dissertation]. Rice University; 2015. Available from: http://hdl.handle.net/1911/95526
Colorado State University
12.
White, Nicholas Andrew.
Enantioselective β-functionalization of enals via N-heterocyclic carbene catalysis.
Degree: PhD, Chemistry, 2016, Colorado State University
URL: http://hdl.handle.net/10217/170358
► A series of δ-nitroesters were synthesized through the N-heterocyclic carbene catalyzed coupling of enals and nitroalkenes. The asymmetric coupling of these substrates via the homoenolate…
(more)
▼ A series of δ-nitroesters were synthesized through the N-heterocyclic carbene catalyzed coupling of enals and nitroalkenes. The
asymmetric coupling of these substrates via the homoenolate pathway afford δ-nitroesters in good yield, diastereoselectivity, and enantioselectivity. This methodology allows for the rapid synthesis of δ-lactams. Using this approach, we synthesized the pharmaceutically relevant piperidines paroxetine and femoxetine. A novel single-electron oxidation pathway for the N-heterocyclic carbene generated Breslow intermediate has been developed. Nitroarenes have been shown to transfer an oxygen from the nitro group to the β-position of an enal in an
asymmetric fashion to generate β-hydroxy esters. This reaction affords desired β-hydroxy ester products in good yield and enantioselectivity and tolerates a wide range of enal substrates. A dimerization of aromatic enals to form 3,4-disubstituted cyclopentanones has been investigated. Using a single-electron oxidant, aromatic enals couple to form cyclopenanone products in good yield, good enantioselectivity, and excellent diastereoselectivity. A cross coupling has also been developed to afford non-symmetrical cyclopentanone products.
Advisors/Committee Members: Rovis, Tomislav (advisor), Kennan, Alan J. (committee member), Chen, Eugene Y.-X. (committee member), Williams, Robert M. (committee member), Kipper, Matt J. (committee member).
Subjects/Keywords: asymmetric; carbene; catalysis; organic
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APA ·
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
White, N. A. (2016). Enantioselective β-functionalization of enals via N-heterocyclic carbene catalysis. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/170358
Chicago Manual of Style (16th Edition):
White, Nicholas Andrew. “Enantioselective β-functionalization of enals via N-heterocyclic carbene catalysis.” 2016. Doctoral Dissertation, Colorado State University. Accessed October 18, 2019.
http://hdl.handle.net/10217/170358.
MLA Handbook (7th Edition):
White, Nicholas Andrew. “Enantioselective β-functionalization of enals via N-heterocyclic carbene catalysis.” 2016. Web. 18 Oct 2019.
Vancouver:
White NA. Enantioselective β-functionalization of enals via N-heterocyclic carbene catalysis. [Internet] [Doctoral dissertation]. Colorado State University; 2016. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10217/170358.
Council of Science Editors:
White NA. Enantioselective β-functionalization of enals via N-heterocyclic carbene catalysis. [Doctoral Dissertation]. Colorado State University; 2016. Available from: http://hdl.handle.net/10217/170358
Colorado State University
13.
Stache, Erin Elizabeth.
Dual nickel- and photoredox-catalyzed enantioselective desymmetrization of meso anhydrides and C-O bond activation via phosphines and photoredox catalysis.
Degree: PhD, Chemistry, 2018, Colorado State University
URL: http://hdl.handle.net/10217/191328
► Described herein is the application of photoredox catalysis in the development of new synthetic methods. A dual nickel- and photoredox catalyzed desymmetrization of meso succinic…
(more)
▼ Described herein is the application of photoredox
catalysis in the development of new synthetic methods. A dual nickel- and photoredox catalyzed desymmetrization of meso succinic anhydrides was developed to generate stereodefined cis keto-acids in high enantioselectivity and diastereoselectivity. The approach employed benzylic radicals as a coupling partner, generated from a photoredox catalyzed single-electron oxidation of benzylic trifluoroborates using an inexpensive organic dye. A unique epimerization event was discovered and the degree of epimerization was rendered tunable by changing catalyst loadings to ultimately form the trans diastereomer preferentially in high enantioeselectivity. A method for the C–O bond activation of aliphatic alcohols and carboxylic acids was developed using phosphines and photoredox
catalysis. This novel reaction platform was used to generate aliphatic or acyl radicals directly from benzylic alcohols and aliphatic and aromatic acids, and with terminal hydrogen atom transfer, afforded the desired deoxygenated alkanes and aldehydes. Additionally, the intermediate acyl radicals could be intercepted in an intramolecular cyclization reaction to generate new lactones, amides and ketones.
Advisors/Committee Members: Rovis, Tomislav (advisor), Doyle, Abigail G. (advisor), Chen, Eugene (committee member), McNally, Andy (committee member), Reynolds, Melissa (committee member), Kipper, Matt (committee member).
Subjects/Keywords: nickel catalysis; photochemistry; organic synthesis; asymmetric catalysis
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APA (6th Edition):
Stache, E. E. (2018). Dual nickel- and photoredox-catalyzed enantioselective desymmetrization of meso anhydrides and C-O bond activation via phosphines and photoredox catalysis. (Doctoral Dissertation). Colorado State University. Retrieved from http://hdl.handle.net/10217/191328
Chicago Manual of Style (16th Edition):
Stache, Erin Elizabeth. “Dual nickel- and photoredox-catalyzed enantioselective desymmetrization of meso anhydrides and C-O bond activation via phosphines and photoredox catalysis.” 2018. Doctoral Dissertation, Colorado State University. Accessed October 18, 2019.
http://hdl.handle.net/10217/191328.
MLA Handbook (7th Edition):
Stache, Erin Elizabeth. “Dual nickel- and photoredox-catalyzed enantioselective desymmetrization of meso anhydrides and C-O bond activation via phosphines and photoredox catalysis.” 2018. Web. 18 Oct 2019.
Vancouver:
Stache EE. Dual nickel- and photoredox-catalyzed enantioselective desymmetrization of meso anhydrides and C-O bond activation via phosphines and photoredox catalysis. [Internet] [Doctoral dissertation]. Colorado State University; 2018. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10217/191328.
Council of Science Editors:
Stache EE. Dual nickel- and photoredox-catalyzed enantioselective desymmetrization of meso anhydrides and C-O bond activation via phosphines and photoredox catalysis. [Doctoral Dissertation]. Colorado State University; 2018. Available from: http://hdl.handle.net/10217/191328
University of St. Andrews
14.
Durrani, Jamie T.
Palladium catalysed asymmetric hydroxy- and alkoxycarbonylation of alkenes
.
Degree: 2015, University of St. Andrews
URL: http://hdl.handle.net/10023/6276
► Palladium catalysed asymmetric hydroxy- and alkoxycarbonylation reactions of alkenes have the potential to deliver valuable chiral carboxylic acid and ester building blocks from cheap feedstocks:…
(more)
▼ Palladium catalysed
asymmetric hydroxy- and alkoxycarbonylation reactions of alkenes have the potential to deliver valuable chiral carboxylic acid and ester building blocks from cheap feedstocks: alkenes, carbon monoxide and water (alcohols in the case of alkoxycarbonylation). Despite the attractive nature of these reactions, extensive research has so far been unable to produce effective catalysts which are capable of controlling both regio- and enantioselectivity.
Building on exciting recent results involving the use of highly enantioselective palladium catalysts derived from Phanephos-type ligands, this research focuses on paracyclophane-diphosphines and their use in
asymmetric hydroxy- and alkoxycarbonylation reactions.
An investigation into reaction conditions analysed several factors, including solvents, CO-pressure, acidic additives and halide sources, to provide optimal activity and selectivities. Two novel electron-poor paracyclophane-diphosphines and their mono- and di-palladium complexes were synthesised and shown to provide exceptional levels of regioselectivity while maintaining high levels of
asymmetric induction. These are the first such examples of hydroxy- or alkoxycarbonylation catalysts to facilitate simultaneous control over both regio- and enantioselectivity. The most effective catalyst was used to promote the reactions of a selection of aryl alkenes and was shown to be tolerant of several different functional groups. A selection of non-symmetric paracyclophane-diphosphine ligands and their palladium complexes were also synthesised and assessed for their performance in hydroxy- and alkoxycarbonylation. We also report the use of Phanephos-type ligands to promote the highly enantioselective hydroxycarbonylation of N-(p-toluenesulfonyl)-3-pyrroline to deliver a chiral proline derivative in high ee.
Advisors/Committee Members: Clarke, Matt (advisor).
Subjects/Keywords: Hydroxycarbonylation;
Alkoxycarbonylation;
Carbonylation;
Asymmetric catalysis;
Homogeneous catalysis
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APA (6th Edition):
Durrani, J. T. (2015). Palladium catalysed asymmetric hydroxy- and alkoxycarbonylation of alkenes
. (Thesis). University of St. Andrews. Retrieved from http://hdl.handle.net/10023/6276
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Durrani, Jamie T. “Palladium catalysed asymmetric hydroxy- and alkoxycarbonylation of alkenes
.” 2015. Thesis, University of St. Andrews. Accessed October 18, 2019.
http://hdl.handle.net/10023/6276.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Durrani, Jamie T. “Palladium catalysed asymmetric hydroxy- and alkoxycarbonylation of alkenes
.” 2015. Web. 18 Oct 2019.
Vancouver:
Durrani JT. Palladium catalysed asymmetric hydroxy- and alkoxycarbonylation of alkenes
. [Internet] [Thesis]. University of St. Andrews; 2015. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10023/6276.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Durrani JT. Palladium catalysed asymmetric hydroxy- and alkoxycarbonylation of alkenes
. [Thesis]. University of St. Andrews; 2015. Available from: http://hdl.handle.net/10023/6276
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Université Catholique de Louvain
15.
Nahra, Fady.
Study of new reactions catalysed by copper(I) complexes : investigation of domino catalysis- and dual catalysis-type reactions.
Degree: 2013, Université Catholique de Louvain
URL: http://hdl.handle.net/2078.1/133426
► In this thesis we are going to first discuss the application of a copper hydride system, which was previously developed in our lab, to new…
(more)
▼ In this thesis we are going to first discuss the application of a copper hydride system, which was previously developed in our lab, to new Michael acceptors bearing a nitrogen group on the double bond. We are equally going to illustrate the development of a new cooperative dual catalysis strategy based on a CuI/Pd0 system. This strategy allowed us to successfully access α-allylated ketones diastereoselectively as well as enantioselectively.
In a later point, we are also going to examine the development of two synthetic pathways to generate unprecedented (NHC)CuI bifluoride complexes. We tested the activity of these complexes in several known CuI-catalyzed reactions, and consequently established the first CuI-catalyzed diastereoselective allylation of (R)-N-tert-butanesulfinyl aldimines. The method enables efficient, simple and general synthesis of enantiomerically enriched homoallylic amines at room temperature in high yields.
(CHIM 3) – UCL, 2013
Advisors/Committee Members: UCL - SST/IMCN/MOST - Molecules, Solids and Reactivity, Riant, Olivier, Gohy, Jean-François, Elias, Benjamin, Poli, Giovanni, Gagosz, Fabien, Van Der Eycken, Johan.
Subjects/Keywords: Asymmetric catalysis; Copper(I); Palladium(0); Domino catalysis; Dual catalysis
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APA (6th Edition):
Nahra, F. (2013). Study of new reactions catalysed by copper(I) complexes : investigation of domino catalysis- and dual catalysis-type reactions. (Thesis). Université Catholique de Louvain. Retrieved from http://hdl.handle.net/2078.1/133426
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Nahra, Fady. “Study of new reactions catalysed by copper(I) complexes : investigation of domino catalysis- and dual catalysis-type reactions.” 2013. Thesis, Université Catholique de Louvain. Accessed October 18, 2019.
http://hdl.handle.net/2078.1/133426.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Nahra, Fady. “Study of new reactions catalysed by copper(I) complexes : investigation of domino catalysis- and dual catalysis-type reactions.” 2013. Web. 18 Oct 2019.
Vancouver:
Nahra F. Study of new reactions catalysed by copper(I) complexes : investigation of domino catalysis- and dual catalysis-type reactions. [Internet] [Thesis]. Université Catholique de Louvain; 2013. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/2078.1/133426.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Nahra F. Study of new reactions catalysed by copper(I) complexes : investigation of domino catalysis- and dual catalysis-type reactions. [Thesis]. Université Catholique de Louvain; 2013. Available from: http://hdl.handle.net/2078.1/133426
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Alberta
16.
Rauniyar, Vivek.
Mechanistic Investigation, Development and Synthetic
Applications of a Catalytic Enantioselective and Diastereoselective
Allylboration Methodology.
Degree: PhD, Department of Chemistry, 2009, University of Alberta
URL: https://era.library.ualberta.ca/files/kw52j8708
► Over the past two decades and continuing on, carbonyl allylation chemistry has been a very useful and popular tool for the stereocontrolled formation of carbon-carbon…
(more)
▼ Over the past two decades and continuing on, carbonyl
allylation chemistry has been a very useful and popular tool for
the stereocontrolled formation of carbon-carbon bonds in the field
of organic synthesis. In the context of natural product synthesis,
the efficiency and status of aldehyde allylboration method is only
matched by the asymmetric and diastereoselective aldol methodology.
Unfortunately, prior to the new millennium, the means to control
the absolute stereoselectivity in the addition of allylic boron
reagents had been restricted to stoichiometric chiral directors,
appended onto the metal center. In 2002, the research groups of
Hall and Miyaura reported a new Lewis acid-catalyzed allylboration
reaction manifold, which raised intriguing mechanistic questions
and also paved the way for a catalytic enantioselective methodology
development. Chapter 2 of this thesis details mechanistic studies
related to the new Lewis acid-catalyzed allylboration. In this
chapter, various control experiments and kinetic studies are
presented, the results of which allowed us to propose a hypothesis
involving the electrophilic boronate activation as the key factor
for the observed rate enhancement. Chapter 3 describes the initial
phase of our research to develop a catalytic enantioselective
allylboration methodology. We discovered that Brønsted acid
catalysts derived from diol•SnCl4 complexes were promising
catalysts for the asymmetric addition of air and moisture stable
and commercially available allylic pinacol boronates. Under this
1st generation catalyst-system, the corresponding homoallylic
alcohols were obtained in moderate to good enantioselectivity and
excellent diastereoselectivity. The development of a novel chiral
Brønsted acid catalyst for the highly enantio- and
diastereoselective allylboration reaction methodology is the single
most important result to come from this thesis. Chapter 4 outlines
the development of the 2nd generation catalyst system. A systematic
study of the diol component of the catalyst system led us to arrive
at a novel diol nicknamed Vivol on behalf of my contribution. The
resulting Brønsted acid derived from Vivol•SnCl4 now provided the
corresponding homoallylic alcohol products in very good to
excellent enantioselectivity. Preliminary mechanistic studies along
with the X-ray diffraction structure of the catalyst system are
also presented. Based on this information, an even better
performaning diol (termed F-Vivol) was developed. This 3rd
generation catalyst system derived from F-Vivol•SnCl4 complex was
shown to display consistently superior reactivity and selectivity
over its 2nd generation predecessor. Chapter 5 describes our
efforts to expand the reagent scope of the Brønsted acid catalyzed
allylboration methodology. Furthermore, this chapter also describes
the successful application of the catalytic process towards the
synthesis of simple and complex molecules. Accordingly, the
preparation and application of the Brønsted acid-catalyzed addition
of 2-bromoallyl boron pinacolate is described.…
Subjects/Keywords: Asymmetric Catalysis, Allylboration, Allylboronate,
Palmerolide A
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APA ·
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APA (6th Edition):
Rauniyar, V. (2009). Mechanistic Investigation, Development and Synthetic
Applications of a Catalytic Enantioselective and Diastereoselective
Allylboration Methodology. (Doctoral Dissertation). University of Alberta. Retrieved from https://era.library.ualberta.ca/files/kw52j8708
Chicago Manual of Style (16th Edition):
Rauniyar, Vivek. “Mechanistic Investigation, Development and Synthetic
Applications of a Catalytic Enantioselective and Diastereoselective
Allylboration Methodology.” 2009. Doctoral Dissertation, University of Alberta. Accessed October 18, 2019.
https://era.library.ualberta.ca/files/kw52j8708.
MLA Handbook (7th Edition):
Rauniyar, Vivek. “Mechanistic Investigation, Development and Synthetic
Applications of a Catalytic Enantioselective and Diastereoselective
Allylboration Methodology.” 2009. Web. 18 Oct 2019.
Vancouver:
Rauniyar V. Mechanistic Investigation, Development and Synthetic
Applications of a Catalytic Enantioselective and Diastereoselective
Allylboration Methodology. [Internet] [Doctoral dissertation]. University of Alberta; 2009. [cited 2019 Oct 18].
Available from: https://era.library.ualberta.ca/files/kw52j8708.
Council of Science Editors:
Rauniyar V. Mechanistic Investigation, Development and Synthetic
Applications of a Catalytic Enantioselective and Diastereoselective
Allylboration Methodology. [Doctoral Dissertation]. University of Alberta; 2009. Available from: https://era.library.ualberta.ca/files/kw52j8708
Georgia State University
17.
Wilkerson, Phillip D.
Synthesis of Chiral N-Heterocyclic Carbene Precursors and Key Intermediates for Catalytic Enantioselective Cyclizations of Conjugated Trienes.
Degree: MS, Chemistry, 2012, Georgia State University
URL: https://scholarworks.gsu.edu/chemistry_theses/49
► Cocatalyzed reactions using Brønsted acids and chiral N-heterocyclic carbenes to yield highly enantioselective products have been reported recently in many journals. The development of…
(more)
▼ Cocatalyzed reactions using Brønsted acids and chiral
N-heterocyclic carbenes to yield highly enantioselective products have been reported recently in many journals. The development of new chiral
N-heterocyclic carbenes is a competitive field among synthetic chemist. In a recent study we found that conjugated trienes could be cyclized using Brønsted acids and chiral
N-heterocyclic carbenes. The synthesis of novel chiral
N-heterocyclic carbene precursors, and the precursors to novel conjugated trienes are reported herein.
Advisors/Committee Members: Hao Xu.
Subjects/Keywords: Asymmetric Catalysis; Catalyst Design; N-heterocyclic carbenes
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
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APA (6th Edition):
Wilkerson, P. D. (2012). Synthesis of Chiral N-Heterocyclic Carbene Precursors and Key Intermediates for Catalytic Enantioselective Cyclizations of Conjugated Trienes. (Thesis). Georgia State University. Retrieved from https://scholarworks.gsu.edu/chemistry_theses/49
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wilkerson, Phillip D. “Synthesis of Chiral N-Heterocyclic Carbene Precursors and Key Intermediates for Catalytic Enantioselective Cyclizations of Conjugated Trienes.” 2012. Thesis, Georgia State University. Accessed October 18, 2019.
https://scholarworks.gsu.edu/chemistry_theses/49.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wilkerson, Phillip D. “Synthesis of Chiral N-Heterocyclic Carbene Precursors and Key Intermediates for Catalytic Enantioselective Cyclizations of Conjugated Trienes.” 2012. Web. 18 Oct 2019.
Vancouver:
Wilkerson PD. Synthesis of Chiral N-Heterocyclic Carbene Precursors and Key Intermediates for Catalytic Enantioselective Cyclizations of Conjugated Trienes. [Internet] [Thesis]. Georgia State University; 2012. [cited 2019 Oct 18].
Available from: https://scholarworks.gsu.edu/chemistry_theses/49.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wilkerson PD. Synthesis of Chiral N-Heterocyclic Carbene Precursors and Key Intermediates for Catalytic Enantioselective Cyclizations of Conjugated Trienes. [Thesis]. Georgia State University; 2012. Available from: https://scholarworks.gsu.edu/chemistry_theses/49
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
National University of Ireland – Galway
18.
Kellehan, David.
Synthesis and Application of Chiral AraBOX ligands for Asymmetric Catalysis
.
Degree: 2012, National University of Ireland – Galway
URL: http://hdl.handle.net/10379/3405
► This thesis deals with the design, synthesis and reactivity of novel 4,4'-bisoxazoline ligands and their metal complexes; (S,S)-MePrAraBOX, (S,S)-PhPrAraBOX, (S,R)-MePrAraBOX, (S,R)-PhPrAraBOX, (S,R)-BnOAcAraBOX and (S,R)-BnOHAraBOX. Metal…
(more)
▼ This thesis deals with the design, synthesis and reactivity of novel 4,4'-bisoxazoline ligands and their metal complexes; (S,S)-MePrAraBOX, (S,S)-PhPrAraBOX, (S,R)-MePrAraBOX, (S,R)-PhPrAraBOX, (S,R)-BnOAcAraBOX and (S,R)-BnOHAraBOX. Metal complexes of these ligands have been applied to transition metal catalysed
asymmetric reactions, in particular
asymmetric Diels Alder, cyclopropanation and allylic alkylation reactions.
A copper(II) complex of (S,R)-PhPrAraBOX catalysed a benchmark Diels Alder reaction in up to 57% ee, the highest enantioselectivity yet achieved for a 4,4'-BOX ligand in a Diels Alder reaction. An ee of 70% was achieved with a copper(I) complex of (S,S)-MePrAraBOX in a benchmark
asymmetric cyclopropanation reaction, which is also the highest enantioselectivity yet achieved for a 4,4'-BOX ligand in these reactions. The ligands were also applied to the
asymmetric allylic alkylation reaction. They were the first 4,4'-BOX ligands to generate enantiocontrol in the reaction, with a palladium complex of (S,S)-MePrAraBOX producing an ee of 72%. The rationalisation of these results, in particular the results relating to the cyclopropanation reaction, are supported by computational studies carried out by colleagues in Zaragoza.
The 4,4'-bisoxazoline ligands (S,R)-BnOAcAraBOX and (S,R)-BnOHAraBOX, which contain secondary binding sites, were applied to the Diels Alder and
asymmetric allylic alkylation reactions with low activity and selectivity. Ligand (S,R)-BnOHAraBOX was also applied to an
asymmetric alkylation of benzaldehyde, showing low conversion and no selectivity.
Chapter One deals with the introduction of the general concepts of
asymmetric synthesis and
asymmetric catalysis. Chapter Two discusses the synthesis of the 4,4'-bisoxazoline ligands and the application of the metal complexes of these ligands to the
asymmetric reactions. Chapter Three contains the full experimental details for the project, including spectral and analytical data.
Advisors/Committee Members: O'Leary, Patrick (advisor).
Subjects/Keywords: Bisoxazoline ligands;
Asymmetric catalysis;
Department of Chemistry
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Kellehan, D. (2012). Synthesis and Application of Chiral AraBOX ligands for Asymmetric Catalysis
. (Thesis). National University of Ireland – Galway. Retrieved from http://hdl.handle.net/10379/3405
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Kellehan, David. “Synthesis and Application of Chiral AraBOX ligands for Asymmetric Catalysis
.” 2012. Thesis, National University of Ireland – Galway. Accessed October 18, 2019.
http://hdl.handle.net/10379/3405.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Kellehan, David. “Synthesis and Application of Chiral AraBOX ligands for Asymmetric Catalysis
.” 2012. Web. 18 Oct 2019.
Vancouver:
Kellehan D. Synthesis and Application of Chiral AraBOX ligands for Asymmetric Catalysis
. [Internet] [Thesis]. National University of Ireland – Galway; 2012. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10379/3405.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Kellehan D. Synthesis and Application of Chiral AraBOX ligands for Asymmetric Catalysis
. [Thesis]. National University of Ireland – Galway; 2012. Available from: http://hdl.handle.net/10379/3405
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of Hong Kong
19.
Ou, Jun.
Asymmetric reactions induced by phase-tagged phosphoric
acid organocatalysts and copper hydride-catalyzed reductions of
unsaturatedthioesters.
Degree: PhD, 2011, University of Hong Kong
URL: Ou,
J.
[欧军].
(2011).
Asymmetric
reactions
induced
by
phase-tagged
phosphoric
acid
organocatalysts
and
copper
hydride-catalyzed
reductions
of
unsaturated
thioesters.
(Thesis).
University
of
Hong
Kong,
Pokfulam,
Hong
Kong
SAR.
Retrieved
from
http://dx.doi.org/10.5353/th_b4784970
;
http://dx.doi.org/10.5353/th_b4784970
;
http://hdl.handle.net/10722/174528
► Two syntheses of non-cross-linked polystyrene-supported TADDOL-based phosphoric acid organocatalyst have been developed. The optimal polymer-supported catalyst 2.29d exhibited comparable catalytic activity to its small molecule…
(more)
▼ Two syntheses of non-cross-linked
polystyrene-supported TADDOL-based phosphoric acid organocatalyst
have been developed. The optimal polymer-supported catalyst 2.29d
exhibited comparable catalytic activity to its small molecule
counterpart in
asymmetric Mannich-type reactions, and the syntheses
of several chiral β-amino esters were demonstrated using 2.29d as
catalyst. However, when this TADDOL-based phosphoric acid was
immobilized on a polystyrene cross-linked with
1,4-bis(4-vinylphenoxy)butane, ie. JandaJelTM, the catalytic
activity diminished in the first recycling and reuse of the
catalyst. Building on the success of the immobilization of chiral
phosphoric acid, a more robust phase-tagged BINOL-based phosphoric
acid organocatalyst was developed. By taking advantage of a
tetraarylphosphonium salt as a solubility-controlling group, a
widely-used BINOL-based phosphoric acid, TRIP (3.1), was introduced
onto a tetraphenylphosphonium salt to produce a phosphonium
salt-tagged phosphoric acid catalyst 3.3e. After systematic
optimizations of reaction conditions, it was found that the
catalyst 3.3e with PF6 as counteranion exhibited the best
performance in terms of enantioselectivity. Catalyst 3.3e was
proved to be highly effective in
asymmetric Friedel-Crafts reaction
of indoles because it was shown to be recyclable and reusable after
six cycles without loss of catalytic activity. Based on our
previous studies on the reduction of unsaturated thioesters
catalyzed by (BDP)CuH, further investigation of ligand effects
revealed that in addition to BDP, dppf was also an effective ligand
for the simple reduction of 5.8. In the stoichiometric reduction of
unsaturated thioester 5.8, dppe and dppf were both efficient
ligands for copper hydride that could convert 5.8 to aldehyde 5.18
in the presence of TMSCl, without the formation of the undesired
enol ester 5.17, which was a major product when stoichiometric
amounts of Stryker’s reagent was employed. When 5.30 bearing both a
saturated and unsaturated thioester was reduced under these
conditions, only the enethioate functional group underwent reaction
to yield the mono-reduced product 5.31 while the saturated
thioester functional group remained inert. The desymmetrizing
reductive aldol reactions of symmetrical keto-enethioates 6.19,
6.22, 6.24 and 6.26 catalyzed by in situ generated chiral copper
hydride were investigated. After a screening of the reaction
conditions, TaniaPhos L8 was found to be the most effective chiral
ligand to achieve high ee and yields. Under the optimum reaction
condition (5 mol% Cu(OAc)-H2O and L8 with 2.0 eq. PhSiH3), a range
of keto-enethioates smoothly underwent desymmetrizing reductive
aldol cyclizations, offering bicyclic or polycyclic
β-hydroxythioesters (6.28a-6.32a, 6.37a-6.47a) in 35- 84% yield and
30-97% ee with high diastereoselectivity. The addition of 5 mol% of
bipyridine as additive resulted in an accelerated reaction rate in
all of the reductions of keto-enethioates. The crystal structure of
the L8-copper bromide complex allowed the…
Advisors/Committee Members: Chiu, P.
Subjects/Keywords: Asymmetric synthesis.; Catalysis.; Organic compounds - Synthesis.
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Ou, J. (2011). Asymmetric reactions induced by phase-tagged phosphoric
acid organocatalysts and copper hydride-catalyzed reductions of
unsaturatedthioesters. (Doctoral Dissertation). University of Hong Kong. Retrieved from Ou, J. [欧军]. (2011). Asymmetric reactions induced by phase-tagged phosphoric acid organocatalysts and copper hydride-catalyzed reductions of unsaturated thioesters. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4784970 ; http://dx.doi.org/10.5353/th_b4784970 ; http://hdl.handle.net/10722/174528
Chicago Manual of Style (16th Edition):
Ou, Jun. “Asymmetric reactions induced by phase-tagged phosphoric
acid organocatalysts and copper hydride-catalyzed reductions of
unsaturatedthioesters.” 2011. Doctoral Dissertation, University of Hong Kong. Accessed October 18, 2019.
Ou, J. [欧军]. (2011). Asymmetric reactions induced by phase-tagged phosphoric acid organocatalysts and copper hydride-catalyzed reductions of unsaturated thioesters. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4784970 ; http://dx.doi.org/10.5353/th_b4784970 ; http://hdl.handle.net/10722/174528.
MLA Handbook (7th Edition):
Ou, Jun. “Asymmetric reactions induced by phase-tagged phosphoric
acid organocatalysts and copper hydride-catalyzed reductions of
unsaturatedthioesters.” 2011. Web. 18 Oct 2019.
Vancouver:
Ou J. Asymmetric reactions induced by phase-tagged phosphoric
acid organocatalysts and copper hydride-catalyzed reductions of
unsaturatedthioesters. [Internet] [Doctoral dissertation]. University of Hong Kong; 2011. [cited 2019 Oct 18].
Available from: Ou, J. [欧军]. (2011). Asymmetric reactions induced by phase-tagged phosphoric acid organocatalysts and copper hydride-catalyzed reductions of unsaturated thioesters. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4784970 ; http://dx.doi.org/10.5353/th_b4784970 ; http://hdl.handle.net/10722/174528.
Council of Science Editors:
Ou J. Asymmetric reactions induced by phase-tagged phosphoric
acid organocatalysts and copper hydride-catalyzed reductions of
unsaturatedthioesters. [Doctoral Dissertation]. University of Hong Kong; 2011. Available from: Ou, J. [欧军]. (2011). Asymmetric reactions induced by phase-tagged phosphoric acid organocatalysts and copper hydride-catalyzed reductions of unsaturated thioesters. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4784970 ; http://dx.doi.org/10.5353/th_b4784970 ; http://hdl.handle.net/10722/174528
University of Hong Kong
20.
Hermeke, Julia.
Chiral phosphonium ion tagged and spiroindane-based
organocatalysts.
Degree: M. Phil., 2011, University of Hong Kong
URL: Hermeke,
J..
(2011).
Chiral
phosphonium
ion
tagged
and
spiroindane-based
organocatalysts.
(Thesis).
University
of
Hong
Kong,
Pokfulam,
Hong
Kong
SAR.
Retrieved
from
http://dx.doi.org/10.5353/th_b4729568
;
http://dx.doi.org/10.5353/th_b4729568
;
http://hdl.handle.net/10722/205871
► The research on asymmetric organocatalysis has been intensifying since the beginning of 2000. The growing interest in this research area is driven by the importance…
(more)
▼ The research on asymmetric organocatalysis has been
intensifying since the beginning of 2000. The growing interest in
this research area is driven by the importance of the chemical
synthesis of enantiomerically pure products. While the general
field of asymmetric organocatalysis has been explored intensively,
the recyclability of organocatalysts has not really been
considered. The attachment of phosphonium ion phase tags to chiral
binaphthyl-based phosphoric acid catalyst and the use of these
materials in a range of organocatalytic asymmetric Friedel-Crafts
reactions of indoles have been studied. Placement of tags at the 3
and 3’ positions of the binaphthyl core, so that they could serve
as steric blocking groups, failed to produce an active catalyst.
However, moving the phosphonium ion groups to the 6 and 6’
positions produced an efficient and enantioselective catalyst.
Aided by the presence of the phase tags, the chiral catalyst was
easily recovered at the end of the reactions, and could be reused
several times, albeit with somewhat decreased efficiency and
enantioselectivity. Furthermore, the synthesis of
1,1’-spirobiindane-7,7’-diol and their spiroindane-based
derivatives have been explored. The (R)-1,1’-spirobiindane-
7,7’-diamine was successfully applied in exo selective asymmetric
Diels-Alder reactions of -unsaturated aldehyde with
cyclopentadiene. However, moderate results aspire further studies
in assay of (R)-1,1’-spirobiindane-7,7’-diamine derivatives, which
bear various bulky groups at the 6 and 6’ positions. Moreover, the
conversion of the SPINOL into a spiroindane ketone unfortunately
failed, which was caused by the sterically crowded structure of the
SPINOL skeleton.
published_or_final_version
Chemistry
Master
Master of Philosophy
Subjects/Keywords: Organic compounds - Synthesis; Asymmetric synthesis; Catalysis
Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Hermeke, J. (2011). Chiral phosphonium ion tagged and spiroindane-based
organocatalysts. (Masters Thesis). University of Hong Kong. Retrieved from Hermeke, J.. (2011). Chiral phosphonium ion tagged and spiroindane-based organocatalysts. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4729568 ; http://dx.doi.org/10.5353/th_b4729568 ; http://hdl.handle.net/10722/205871
Chicago Manual of Style (16th Edition):
Hermeke, Julia. “Chiral phosphonium ion tagged and spiroindane-based
organocatalysts.” 2011. Masters Thesis, University of Hong Kong. Accessed October 18, 2019.
Hermeke, J.. (2011). Chiral phosphonium ion tagged and spiroindane-based organocatalysts. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4729568 ; http://dx.doi.org/10.5353/th_b4729568 ; http://hdl.handle.net/10722/205871.
MLA Handbook (7th Edition):
Hermeke, Julia. “Chiral phosphonium ion tagged and spiroindane-based
organocatalysts.” 2011. Web. 18 Oct 2019.
Vancouver:
Hermeke J. Chiral phosphonium ion tagged and spiroindane-based
organocatalysts. [Internet] [Masters thesis]. University of Hong Kong; 2011. [cited 2019 Oct 18].
Available from: Hermeke, J.. (2011). Chiral phosphonium ion tagged and spiroindane-based organocatalysts. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4729568 ; http://dx.doi.org/10.5353/th_b4729568 ; http://hdl.handle.net/10722/205871.
Council of Science Editors:
Hermeke J. Chiral phosphonium ion tagged and spiroindane-based
organocatalysts. [Masters Thesis]. University of Hong Kong; 2011. Available from: Hermeke, J.. (2011). Chiral phosphonium ion tagged and spiroindane-based organocatalysts. (Thesis). University of Hong Kong, Pokfulam, Hong Kong SAR. Retrieved from http://dx.doi.org/10.5353/th_b4729568 ; http://dx.doi.org/10.5353/th_b4729568 ; http://hdl.handle.net/10722/205871
Penn State University
21.
Shang, Gao.
THE DEVELOPMENT AND APPLICATIONS OF ELECTRON-RICH
PHOSPHORUS-CONTAINING LIGANDS IN ASYMMETRIC HYDROGENATION.
Degree: PhD, Chemistry, 2008, Penn State University
URL: https://etda.libraries.psu.edu/catalog/8189
► Catalytic asymmetric transformations are important synthetic approaches for the preparation of enantiomerically enriched products. Among numerous methodologies developed in the past few decades, transition metal-catalyzed…
(more)
▼ Catalytic asymmetric transformations are important
synthetic approaches for the preparation of enantiomerically
enriched products. Among numerous methodologies developed in the
past few decades, transition metal-catalyzed asymmetric
hydrogenation has been demonstrated as one of the most efficient
methods. In this particular area, two directions of research can be
found. One is the exploration of unsaturated prochiral molecules
that can serve as hydrogenation substrates and produce important
chiral product using current available catalysts. On the other
hand, the continuous development of novel chiral ligands, usually
phosphorus containing ligands, also plays a key role in improving
the efficiency of this methodology. It is interesting to note that
an important discovery in one direction can frequently promote the
studies in the other. These two directions are also the main
focuses of this dissertation. From chapter 2 to chapter 4, three
kinds of challenging substrates were studied in transition
metal-catalyzed hydrogenation reaction and important chiral
products were obtained in good yields and selectivities. In chapter
2, A highly enantioselective synthesis of arylglycine derivatives
through Rh-bisphosphine catalyzed asymmetric hydrogenation is
presented. The stable N-PMP protected α-aryl imino esters
were synthesized from the corresponding α-ketoesters in
high yields. Using a rhodium catalyst with an electron rich and
rigid Rh-TangPhos, high ee values have been achieved in the
hydrogenation of N-PMP protected α-aryl imino esters. An
efficient Pd-bisphosphine catalyzed hydrogenation of
unfunctionalized N-tosylimines is presented in chapter 3.
N-tosylimines could be synthesized from corresponding ketones
exclusively in E configuration and readily served as substrates for
asymmetric hydrogenation. Excellent enantioselectivities (up to 99%
ee) and conversions (up to >99%) could be achieved when
Pd(OCOCF3)2 complexed with an electron-rich rigid chiral
bisphosphine, TangPhos, was employed. A variety of aromatic,
aliphatic and cyclic chiral amines can be prepared from this
methodology. In chapter 4, two β-receptor agonists
(-)-denopamine and (-)-arbutamine were prepared in good yields and
enantioselectivities via asymmetric hydrogenation of unprotected
amino ketones for the first time using Rh catalysts bearing
electron-rich phosphine ligands. A series of -primary
and secondary amino ketones were synthesized and hydrogenated to
produce various 1,2-amino alcohols in good yields and
enantioselectivies. This Rh-electron rich phosphine catalyzed
asymmetric hyderogenation represents one of the most promising and
convenient approaches to the asymmetric synthesis of chiral amino
alcohols. Despite the high diversity of chiral phosphorus ligands
and their great achievement on various transformations, most of
them are extremely air sensitive. The tedious synthesis and
handling procedures limit them from being widely used in industrial
applications. Progress in the development of new generation of air…
Subjects/Keywords: Asymmetric hydrogenation; Catalysis; chiral
phosphorus-containing ligands
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APA (6th Edition):
Shang, G. (2008). THE DEVELOPMENT AND APPLICATIONS OF ELECTRON-RICH
PHOSPHORUS-CONTAINING LIGANDS IN ASYMMETRIC HYDROGENATION. (Doctoral Dissertation). Penn State University. Retrieved from https://etda.libraries.psu.edu/catalog/8189
Chicago Manual of Style (16th Edition):
Shang, Gao. “THE DEVELOPMENT AND APPLICATIONS OF ELECTRON-RICH
PHOSPHORUS-CONTAINING LIGANDS IN ASYMMETRIC HYDROGENATION.” 2008. Doctoral Dissertation, Penn State University. Accessed October 18, 2019.
https://etda.libraries.psu.edu/catalog/8189.
MLA Handbook (7th Edition):
Shang, Gao. “THE DEVELOPMENT AND APPLICATIONS OF ELECTRON-RICH
PHOSPHORUS-CONTAINING LIGANDS IN ASYMMETRIC HYDROGENATION.” 2008. Web. 18 Oct 2019.
Vancouver:
Shang G. THE DEVELOPMENT AND APPLICATIONS OF ELECTRON-RICH
PHOSPHORUS-CONTAINING LIGANDS IN ASYMMETRIC HYDROGENATION. [Internet] [Doctoral dissertation]. Penn State University; 2008. [cited 2019 Oct 18].
Available from: https://etda.libraries.psu.edu/catalog/8189.
Council of Science Editors:
Shang G. THE DEVELOPMENT AND APPLICATIONS OF ELECTRON-RICH
PHOSPHORUS-CONTAINING LIGANDS IN ASYMMETRIC HYDROGENATION. [Doctoral Dissertation]. Penn State University; 2008. Available from: https://etda.libraries.psu.edu/catalog/8189
University of California – Berkeley
22.
Neel, Andrew James.
Toward the Rational Design of Asymmetric Catalysts using Attractive Non-Covalent Interactions and Design Elements.
Degree: Chemistry, 2016, University of California – Berkeley
URL: http://www.escholarship.org/uc/item/34d2396n
► Throughout my doctoral studies, I have endeavored to address the question of how to rationally design chiral catalysts to control enantioselectivity in a predictable fashion.…
(more)
▼ Throughout my doctoral studies, I have endeavored to address the question of how to rationally design chiral catalysts to control enantioselectivity in a predictable fashion. To approach this problem, I have focused on the strategic implementation of attractive non-covalent interactions between catalysts and their substrates at the enantiodetermining transition state. A significant portion of this work involved the development of an approach to elucidating the structural origins of selectivity in complex data sets, with an eye towards rational catalyst design. The insights gained from these studies constitute the subject matter of this dissertation.Chapter 1 provides an overview of a subset of attractive non-covalent interactions involving aromatic rings. Examples are highlighted in which these interactions have been characterized in the ground state with the explicit intention of quantifying their strengths and geometric requirements. Using the lessons learned from these reports, case studies are presented in which the interactions under discussion have been leveraged to catalyze chemical reactions via the paradigm of transition state stabilization. The insight gleaned from this literature survey is intended to provide a framework for the discussion of the catalyst design concepts outlined in the following chapters.Chapter 2 describes the development of a novel class of axially chiral triazole containing phosphoric acid catalysts designed to impart enantioselectivity via attractive non-covalent interactions with a substrate at the enantiodetermining TS. This strategy stands in contrast to that typically discussed in the literature in which catalyst steric bulk is frequently invoked to rationalize asymmetric induction. Using this newly prepared catalyst library, an enantioselective cross dehydrogenative coupling was developed within the conceptual framework of the Toste group’s strategy of chiral anion phase transfer catalysis. Preliminary experiments suggested that the triazole substituents played a role in the determination of asymmetric induction beyond steric bulk, as initially hypothesized. The third chapter describes our efforts to elucidate the structural origins of enantioselectivity in the oxidative coupling reaction presented in Chapter 2. By obtaining an enantioselectivity data set based on strategically modulated catalysts and substrates, we applied linear regression techniques to correlate our experimental data with molecular descriptors describing the structural variation throughout the data set. The resulting models, along with the overall enantioselectivity trends, were used to develop intuitively sensible mechanistic hypotheses that were subsequently tested through the application of new catalysts specifically tailored to address them. Based on the hypothesis that the triazole catalysts were engaged in enantiodetermining interactions with the substrates at the TS, we rationally designed catalysts that afforded the products with the highest enantiomeric excesses reported to…
Subjects/Keywords: Chemistry; Asymmetric Catalysis; Organic Synthesis; Organocatalysis
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APA (6th Edition):
Neel, A. J. (2016). Toward the Rational Design of Asymmetric Catalysts using Attractive Non-Covalent Interactions and Design Elements. (Thesis). University of California – Berkeley. Retrieved from http://www.escholarship.org/uc/item/34d2396n
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Neel, Andrew James. “Toward the Rational Design of Asymmetric Catalysts using Attractive Non-Covalent Interactions and Design Elements.” 2016. Thesis, University of California – Berkeley. Accessed October 18, 2019.
http://www.escholarship.org/uc/item/34d2396n.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Neel, Andrew James. “Toward the Rational Design of Asymmetric Catalysts using Attractive Non-Covalent Interactions and Design Elements.” 2016. Web. 18 Oct 2019.
Vancouver:
Neel AJ. Toward the Rational Design of Asymmetric Catalysts using Attractive Non-Covalent Interactions and Design Elements. [Internet] [Thesis]. University of California – Berkeley; 2016. [cited 2019 Oct 18].
Available from: http://www.escholarship.org/uc/item/34d2396n.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Neel AJ. Toward the Rational Design of Asymmetric Catalysts using Attractive Non-Covalent Interactions and Design Elements. [Thesis]. University of California – Berkeley; 2016. Available from: http://www.escholarship.org/uc/item/34d2396n
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
National University of Ireland – Galway
23.
Mc Cleary, Nadine.
Design, synthesis and catalytic activity of novel oxazoline based ligands.
Degree: 2015, National University of Ireland – Galway
URL: http://hdl.handle.net/10379/5210
► This thesis can be viewed as two separate studies. Firstly, the design, synthesis and catalytic activity of novel 2-pyridyl mono(oxazoline). A family of mono(oxazoline) ligands…
(more)
▼ This thesis can be viewed as two separate studies. Firstly, the design, synthesis and catalytic activity of novel 2-pyridyl mono(oxazoline). A family of mono(oxazoline) ligands were developed in which the 5-poition is substituted with various substituted esters. These ligands were then applied as organocatalysts in an asymmetric hydrosilylation reaction and an asymmetric allylation reaction.
Mono(oxazoline) ligands catalysed a benchmark hydrosilylation reaction and ee's of up to 46 to 48% were obtained. The ligands in which either the adamantyl ester, p nitro phenyl ester, p-chloro phenyl ester or the p-methyl phenyl ester were present afforded these results. Use of the ligands in a benchmark allylation reaction showed low conversions.
Preliminary modifications to the backbone structure were also undertaken in order to ascertain the dendicity of the ligands. It was found the ligands coordinate in a bidentate fashion.
The second part of the this study involved the design and attempted synthesis of 2nd generation 4,4'-bis(oxazoline) ligands. Structural modifications were proposed in order to increase selectivity from that of the first generation of ligands within this class. Our first proposed modification was the addition of secondary binding sites on the pendant groups on the ligand. Attempted ligand formation a novel one-pot deprotection-activation-ring-closure (DARC) reaction, was not successful.
The second proposed modification was the installation of a functionalised bridgehead. Racemisation issues lead to the formation of diastereomeric pairs in which separate was not possible, and the synthesis of the desired ligand proved unsuccessful. This and other synthetic results are discussed herein.
2018-08-14
Advisors/Committee Members: O'Leary, Patrick, College of Science, NUI Galway.
Subjects/Keywords: Asymmetric catalysis; Organic synthesis; School of Chemistry
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APA (6th Edition):
Mc Cleary, N. (2015). Design, synthesis and catalytic activity of novel oxazoline based ligands. (Thesis). National University of Ireland – Galway. Retrieved from http://hdl.handle.net/10379/5210
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Mc Cleary, Nadine. “Design, synthesis and catalytic activity of novel oxazoline based ligands.” 2015. Thesis, National University of Ireland – Galway. Accessed October 18, 2019.
http://hdl.handle.net/10379/5210.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Mc Cleary, Nadine. “Design, synthesis and catalytic activity of novel oxazoline based ligands.” 2015. Web. 18 Oct 2019.
Vancouver:
Mc Cleary N. Design, synthesis and catalytic activity of novel oxazoline based ligands. [Internet] [Thesis]. National University of Ireland – Galway; 2015. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10379/5210.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Mc Cleary N. Design, synthesis and catalytic activity of novel oxazoline based ligands. [Thesis]. National University of Ireland – Galway; 2015. Available from: http://hdl.handle.net/10379/5210
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Massey University
24.
Wang, Jingjing.
A study of new planar chiral monophosphine ligands based on [2.2]paracyclophane and their use in catalysis : Chemistry, Institute of Fundamental Sciences, Massey University : Masters thesis under the supervision of Dr. Gareth J. Rowlands
.
Degree: 2011, Massey University
URL: http://hdl.handle.net/10179/2900
► The Suzuki-Miyaura coupling reaction is one of the most powerful methods for the construction of biaryls. The biaryl motif has great importance in pharmaceutical, agrichemical…
(more)
▼ The Suzuki-Miyaura coupling reaction is one of the most powerful methods for the
construction of biaryls. The biaryl motif has great importance in pharmaceutical,
agrichemical and material science industries, and is often axially chiral. The outcome of a
Suzuki-Miyaura coupling reaction can be influenced by many factors, but the ligand plays the
most vital role. A large number of ligands have been developed, including many chiral
ligands for asymmetric reactions. While ligand design has focused on molecules containing
either central or axial chirality, little has been focused on planar chiral ligands.
In this project, three new ligands based on the [2.2]paracyclophane backbone have been
designed, pseudo-ortho substituted monophosphines (L1 and L2), secondary phosphine oxide
and arylindolyl phosphine ligands (L3 and L4). Unfortunately, similar analogues of L1 and
L2 were reported before our results, and a synthesis route to the secondary phosphine oxide
ligands was not achieved. The use of L1 in gold mediated cyclisation was investigated, which
concluded that L1 was not suitable for this kind of reaction. However, arylindolyl phosphine
ligands were prepared successfully, and produced promising preliminary results in achiral
Suzuki-Miyaura coupling reactions.
Interesting X-ray crystallography structure of brominated indole is discussed.
Subjects/Keywords: Asymmetric catalysis;
Ligands;
Chirality;
Paracyclophanes;
Biaryls;
Phosphine
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APA ·
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MLA ·
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CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Wang, J. (2011). A study of new planar chiral monophosphine ligands based on [2.2]paracyclophane and their use in catalysis : Chemistry, Institute of Fundamental Sciences, Massey University : Masters thesis under the supervision of Dr. Gareth J. Rowlands
. (Thesis). Massey University. Retrieved from http://hdl.handle.net/10179/2900
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Wang, Jingjing. “A study of new planar chiral monophosphine ligands based on [2.2]paracyclophane and their use in catalysis : Chemistry, Institute of Fundamental Sciences, Massey University : Masters thesis under the supervision of Dr. Gareth J. Rowlands
.” 2011. Thesis, Massey University. Accessed October 18, 2019.
http://hdl.handle.net/10179/2900.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Wang, Jingjing. “A study of new planar chiral monophosphine ligands based on [2.2]paracyclophane and their use in catalysis : Chemistry, Institute of Fundamental Sciences, Massey University : Masters thesis under the supervision of Dr. Gareth J. Rowlands
.” 2011. Web. 18 Oct 2019.
Vancouver:
Wang J. A study of new planar chiral monophosphine ligands based on [2.2]paracyclophane and their use in catalysis : Chemistry, Institute of Fundamental Sciences, Massey University : Masters thesis under the supervision of Dr. Gareth J. Rowlands
. [Internet] [Thesis]. Massey University; 2011. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10179/2900.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Wang J. A study of new planar chiral monophosphine ligands based on [2.2]paracyclophane and their use in catalysis : Chemistry, Institute of Fundamental Sciences, Massey University : Masters thesis under the supervision of Dr. Gareth J. Rowlands
. [Thesis]. Massey University; 2011. Available from: http://hdl.handle.net/10179/2900
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universitat Rovira i Virgili
25.
Alza Barrios, Esther.
Approaches to asymmetric catalysis with polymer-supported pyrrolidines.
Degree: Departament de Química Analítica i Química Orgànica, 2011, Universitat Rovira i Virgili
URL: http://hdl.handle.net/10803/37362
► The present research project developed is focused in the immobilization of catalytic systems allowing the formation of carbon-carbon and carbonheteroatom bonds through enantioselective procedures with…
(more)
▼ The present research project developed is focused in the immobilization of
catalytic systems allowing the formation of carbon-carbon and carbonheteroatom
bonds through enantioselective procedures with improved
sustainability characteristics (suppression of catalyst separation steps,
preferential use of water as a solvent under aerobic conditions, avoidance of
protecting groups and, hence, of protection and deprotection steps). In
particular, the study is directed towards the organocatalysis field, although
also
asymmetric catalytic processes mediated by metal complexes have been
developed. The approach introduced by our group combines the
optimization of the catalytic properties of the ligands, which is greatly
facilitated by their modular nature, with a design principle consisting in
performing the anchoring to the polymer through auxiliary functional
groups, positioned on the ligand molecule for minimal perturbation of the
catalytic site. In this manner, we have been able to develop polymersupported
ligands that do not show any decrease in catalytic activity or in
enantioselectivity with respect to their homogeneous counterparts. The
usual anchoring strategy used is the Cu-catalyzed azide/alkyne 1,3 dipolar
cycloaddition. In this manner, in this work proline and pyrrolidine
derivatives have been synthesized to catalyze organic transformations via
enamine and iminium ion mechanisms as Mannich or Michael reactions.
Organocatalytic cascade process has also been reported as useful method
for the preparation of highly functionalized cyclohexane derivatives in a
straightforward and efficient manner and the use of supported
organocatalysts has allowed us to implement this reactions not only in batch
processes but also in continuous flow conditions obtaining large amount of
desired product with high enantiopurity.
As have been mentioned,
asymmetric catalysis mediated by metal complexes
has been investigated. One project collect the study of the
asymmetric
reduction of ketones with borane and oxazaborolidine type catalysts as
aminoalcohols in homogeneous phase and the application of
diphenylprolinol derivatives supported on polymers by click-chemistry or by
direct nucleophilic substitution to the Merrifield resin. It is verified
experimentally that the triazole ring formed by anchoring the monomer to
the polymer matrix by click reaction has an important role in the selectivity
of the catalyst because leads to a not enantioselective path due to the boron
coordination to the triazole. When triazole ring is not present, aromatic
ketones are reduced with high enantioselectivities (90-99%) and complete
conversion after 30 minutes of reaction with qualitative yield because the
easy removing of the catalyst from the product by filtration.
Also a series of new modular Ru/aminoalcohol systems has been developed
and used as enantioselective catalysts in the
asymmetric transfer
hydrogenation reaction of ketones in both water and 2-propanol. The
catalytic behaviour exhibited in these two media…
Advisors/Committee Members: [email protected] (authoremail), false (authoremailshow), Pericàs i Brondo, Miquel A. (Miquel Àngel) (director), Sayalero, Sonia (codirector), true (authorsendemail).
Subjects/Keywords: Asymmetric catalysis; Organocatalysis; Supported catalysts; 54; 547
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APA ·
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APA (6th Edition):
Alza Barrios, E. (2011). Approaches to asymmetric catalysis with polymer-supported pyrrolidines. (Thesis). Universitat Rovira i Virgili. Retrieved from http://hdl.handle.net/10803/37362
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Alza Barrios, Esther. “Approaches to asymmetric catalysis with polymer-supported pyrrolidines.” 2011. Thesis, Universitat Rovira i Virgili. Accessed October 18, 2019.
http://hdl.handle.net/10803/37362.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Alza Barrios, Esther. “Approaches to asymmetric catalysis with polymer-supported pyrrolidines.” 2011. Web. 18 Oct 2019.
Vancouver:
Alza Barrios E. Approaches to asymmetric catalysis with polymer-supported pyrrolidines. [Internet] [Thesis]. Universitat Rovira i Virgili; 2011. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10803/37362.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Alza Barrios E. Approaches to asymmetric catalysis with polymer-supported pyrrolidines. [Thesis]. Universitat Rovira i Virgili; 2011. Available from: http://hdl.handle.net/10803/37362
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Universidade Nova
26.
Zalewska, Karolina Anna Maria.
Development of novel ionic liquids based on biological molecules.
Degree: 2015, Universidade Nova
URL: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/14075
► Ionic Liquids (ILs) belong to a class of compounds with unusual properties: very low vapour pressure; high chemical and thermal stability and the ability to…
(more)
▼ Ionic Liquids (ILs) belong to a class of compounds with unusual properties: very low vapour pressure; high chemical and thermal stability and the ability to dissolve a wide range of substances. A new field in research is evaluating the possibility to use natural chiral biomolecules for the preparation of chiral ionic liquids (CILs). This important challenge in synthetic chemistry can open new avenues of research in order to avoid some problems related with the intrinsic biodegradability and toxicity associated to conventional ILs.
The research work developed aimed for the synthesis of CILs, their characterization and possible applications, based on biological moieties used either as chiral cations or anions, depending on the synthetic manipulation of the derivatives. Overall, a total of 28 organic salts, including CILs were synthesized: 9 based on L-cysteine derivatives, 12 based on L-proline, 3 based on nucleosides and 4 based on nucleotides. All these new CILs were completely characterized and their chemical and physical properties were evaluated. Some CILs based on L-cysteine have been applied for discrimination processes, including resolution of racemates and as a chiral catalyst for
asymmetric Aldol condensation. L-proline derived CILs were also studied as chiral catalysts for Michael reaction.
In parallel, the interactions of macrocyclic oligosugars called cyclodextrins (CDs) with several ILs were studied. It was possible to improve the solubility of CDs in water and serum. Additionally, fatty acids and steroids showed an increase in water solubility when ILs-CDs systems were used. The development of efficient and selective ILs-CDs systems is indispensable to expand the range of their applications in host-guest interactions, drug delivery systems or catalytic reactions.
Novel salts derived from nucleobases were used in order to enhance the fluorescence in aqueous solution.
Additionally, preliminary studies regarding ethyl lactate as an alternative solvent for
asymmetric organocatalysis were performed.
Advisors/Committee Members: Branco, Luís.
Subjects/Keywords: Ionic liquids; Biological molecules; Chirality; Asymmetric catalysis
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APA ·
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APA (6th Edition):
Zalewska, K. A. M. (2015). Development of novel ionic liquids based on biological molecules. (Thesis). Universidade Nova. Retrieved from http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/14075
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Zalewska, Karolina Anna Maria. “Development of novel ionic liquids based on biological molecules.” 2015. Thesis, Universidade Nova. Accessed October 18, 2019.
http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/14075.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Zalewska, Karolina Anna Maria. “Development of novel ionic liquids based on biological molecules.” 2015. Web. 18 Oct 2019.
Vancouver:
Zalewska KAM. Development of novel ionic liquids based on biological molecules. [Internet] [Thesis]. Universidade Nova; 2015. [cited 2019 Oct 18].
Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/14075.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Zalewska KAM. Development of novel ionic liquids based on biological molecules. [Thesis]. Universidade Nova; 2015. Available from: http://www.rcaap.pt/detail.jsp?id=oai:run.unl.pt:10362/14075
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Mississippi State University
27.
Chakraborty, Amarraj.
The method development for synthesizing chiral CCC-NHC Zr pincer complexes.
Degree: MS, Chemistry, 2015, Mississippi State University
URL: http://sun.library.msstate.edu/ETD-db/theses/available/etd-08062015-162047/
;
► There are numerous classes of N-heterocyclic carbenes (NHCs) that have been synthesized since the discovery of stable NHCs in 1988. Their application as ligands…
(more)
▼ There are numerous classes of N-heterocyclic carbenes (NHCs) that have been synthesized since the discovery of stable NHCs in 1988. Their application as ligands in metal complexes has received much attention because of their strong sigma-donor and poor pi-acceptor properties. Within these NHC metal complexes, we are interested in studying zirconium metal complexes with pincer NHC ligands. Recently, achiral CCC-NHC pincer zirconium complexes were synthesized and their catalytic activity in intramolecular hydroamination of aminoalkenes were reported.
Herein is reported new reaction conditions which yield pure, chiral CCC-NHC Zr pincer mono(amido) dibromo complex. The enantiopure crystal structure of the same complex is reported. Attempts to synthesize chiral CCC-NHC Zr pincer bis- and tris- amido complexes with the iodo salt of the ligand precursor are summarized. Moreover, syntheses of chiral bis(imidazolinium) ligand precursors with different counter anions are reported with optimized reaction conditions.
Advisors/Committee Members: Keith T. Mead (chair), Andrzej Sygula (committee member), Joseph Emerson (committee member).
Subjects/Keywords: synthesis; Zr chemistry; organometallic chemistry; asymmetric catalysis
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APA (6th Edition):
Chakraborty, A. (2015). The method development for synthesizing chiral CCC-NHC Zr pincer complexes. (Masters Thesis). Mississippi State University. Retrieved from http://sun.library.msstate.edu/ETD-db/theses/available/etd-08062015-162047/ ;
Chicago Manual of Style (16th Edition):
Chakraborty, Amarraj. “The method development for synthesizing chiral CCC-NHC Zr pincer complexes.” 2015. Masters Thesis, Mississippi State University. Accessed October 18, 2019.
http://sun.library.msstate.edu/ETD-db/theses/available/etd-08062015-162047/ ;.
MLA Handbook (7th Edition):
Chakraborty, Amarraj. “The method development for synthesizing chiral CCC-NHC Zr pincer complexes.” 2015. Web. 18 Oct 2019.
Vancouver:
Chakraborty A. The method development for synthesizing chiral CCC-NHC Zr pincer complexes. [Internet] [Masters thesis]. Mississippi State University; 2015. [cited 2019 Oct 18].
Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-08062015-162047/ ;.
Council of Science Editors:
Chakraborty A. The method development for synthesizing chiral CCC-NHC Zr pincer complexes. [Masters Thesis]. Mississippi State University; 2015. Available from: http://sun.library.msstate.edu/ETD-db/theses/available/etd-08062015-162047/ ;
University of St. Andrews
28.
Joannesse, Caroline.
Isothiourea-promoted O- to C-carboxyl transfer reactions
.
Degree: 2011, University of St. Andrews
URL: http://hdl.handle.net/10023/3109
► This thesis describes an extensive investigation of the O- to C-carboxyl transfer of oxazolyl carbonates using isothioureas as Lewis base catalysts. The structural requirements of…
(more)
▼ This thesis describes an extensive investigation of the O- to C-carboxyl transfer of oxazolyl carbonates using isothioureas as Lewis base catalysts. The structural requirements of simple bicyclic amidines and isothioureas to promote this transformation have been investigated, showing that the catalytic efficiency and product distribution of these reactions are markedly affected by the catalyst structure. The optimal isothiourea catalyst was efficiently applied to the rearrangement of a wide range of oxazolyl, benzofuranyl and indolyl carbonates. The structural motif of tetrahydropyrimidine-based isothioureas has then been evaluated in order to develop an
asymmetric variant of the O- to C-carboxyl transfer of oxazolyl carbonates. A number of chiral isothioureas bearing stereodirecting groups in C(2) and/or C(3) have been synthesised and used in this rearrangement, showing that a C(2)-stereodirecting unit is essential for high enantioselectivity, with an additional C(3)-substituent increasing the reactivity. The optimal chiral C(2)-substituted isothioureas identified are general and efficient
asymmetric catalysts for O- to C-carboxyl transfer of oxazolyl carbonates, generating a quaternary stereocentre with high enantioselectivity (up to 94% ee). The origin of the enantioselectivity of this process has been probed mechanistically and rationalised computationally. Having gained an insight into the structural motifs of isothioureas required to impart good catalytic activity and
asymmetric induction in the O- to C-carboxyl transfer of oxazolyl carbonates, the mechanism of this reaction was probed using kinetic and mechanistic experiments. ¹⁹F NMR spectroscopic analysis allowed the evolution of product, by-product and intermediate throughout the reaction to be monitored while a number of crossover and stability experiments gave additional information about the catalytic cycle. Extension to a related system has been demonstrated with the O- to C-carboxyl transfer of furanyl carbonates, producing a mixture of α- and γ-butenolides depending on the nature of the Lewis base employed. DMAP gives a mixture of both regioisomers with a preference for the α-regioisomer, while NHCs lead predominantly to the
γ-regioisomer. Chiral isothioureas have been used to promote this rearrangement, giving the major α-regioisomer with good enantioselectivity (up to 83% ee). To quantify the different reactivities observed with these isothioureas, their nucleophilicities and Lewis basicities using the stopped-flow technique have been determined. Finally, model studies toward the synthesis of the natural product calcaridine A, using the methodology developed herein, have been investigated.
Advisors/Committee Members: Smith, Andrew David (advisor).
Subjects/Keywords: Organocatalysis;
Isothiourea;
Asymmetric catalysis;
Steglich rearrangement
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APA ·
Chicago ·
MLA ·
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CSE |
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APA (6th Edition):
Joannesse, C. (2011). Isothiourea-promoted O- to C-carboxyl transfer reactions
. (Thesis). University of St. Andrews. Retrieved from http://hdl.handle.net/10023/3109
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Joannesse, Caroline. “Isothiourea-promoted O- to C-carboxyl transfer reactions
.” 2011. Thesis, University of St. Andrews. Accessed October 18, 2019.
http://hdl.handle.net/10023/3109.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Joannesse, Caroline. “Isothiourea-promoted O- to C-carboxyl transfer reactions
.” 2011. Web. 18 Oct 2019.
Vancouver:
Joannesse C. Isothiourea-promoted O- to C-carboxyl transfer reactions
. [Internet] [Thesis]. University of St. Andrews; 2011. [cited 2019 Oct 18].
Available from: http://hdl.handle.net/10023/3109.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Joannesse C. Isothiourea-promoted O- to C-carboxyl transfer reactions
. [Thesis]. University of St. Andrews; 2011. Available from: http://hdl.handle.net/10023/3109
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
University of South Florida
29.
Tao, Jingran.
Asymmetric Nitrene Transfer Reactions with Azides via Co(II)-Based Metalloradical Catalysis (MRC).
Degree: 2013, University of South Florida
URL: https://scholarcommons.usf.edu/etd/4590
► Asymmetric nitrene transfer reactions via metalloradical catalysis (MRC) with azides has attracted research interest because of its fundamental and practical importance. The resulting nitrogen-containing units…
(more)
▼ Asymmetric nitrene transfer reactions via metalloradical catalysis (MRC) with
azides has attracted research interest because of its fundamental and practical importance.
The resulting nitrogen-containing units are recurrent motifs in biologically important
molecules and can serve as versatile precursors in organic synthesis.
The [Co(D2-Por*)] have emerged as a new class of catalysts for asymmetric
aziridination and C-H amination. These metalloradical catalysts have been shown to be
highly effective for the asymmetric intermolecular aziridination of a broad scope of
substrates with different classes of azides with excellent to good enantioselectivity. The
intramolecular C-H amination utilizing various azides can allow for the construction of
diverse nitrogen containing heterocyclic compounds.
Subjects/Keywords: asymmetric; azide; aziridination; catalysis; cobalt; porphyrin; Chemistry
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Record Details
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APA ·
Chicago ·
MLA ·
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CSE |
Export
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APA (6th Edition):
Tao, J. (2013). Asymmetric Nitrene Transfer Reactions with Azides via Co(II)-Based Metalloradical Catalysis (MRC). (Thesis). University of South Florida. Retrieved from https://scholarcommons.usf.edu/etd/4590
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Chicago Manual of Style (16th Edition):
Tao, Jingran. “Asymmetric Nitrene Transfer Reactions with Azides via Co(II)-Based Metalloradical Catalysis (MRC).” 2013. Thesis, University of South Florida. Accessed October 18, 2019.
https://scholarcommons.usf.edu/etd/4590.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
MLA Handbook (7th Edition):
Tao, Jingran. “Asymmetric Nitrene Transfer Reactions with Azides via Co(II)-Based Metalloradical Catalysis (MRC).” 2013. Web. 18 Oct 2019.
Vancouver:
Tao J. Asymmetric Nitrene Transfer Reactions with Azides via Co(II)-Based Metalloradical Catalysis (MRC). [Internet] [Thesis]. University of South Florida; 2013. [cited 2019 Oct 18].
Available from: https://scholarcommons.usf.edu/etd/4590.
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Council of Science Editors:
Tao J. Asymmetric Nitrene Transfer Reactions with Azides via Co(II)-Based Metalloradical Catalysis (MRC). [Thesis]. University of South Florida; 2013. Available from: https://scholarcommons.usf.edu/etd/4590
Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation
Wayne State University
30.
Averill, Derek James.
Lanthanide-Based Precatalysts For Carbon-Carbon Bond-Forming Reactions In Aqueous Media.
Degree: PhD, Chemistry, 2014, Wayne State University
URL: https://digitalcommons.wayne.edu/oa_dissertations/1084
► The formation of carbon-carbon bonds is of great interest to synthetic chemists because these bonds make up the majority of biologically active compounds. The…
(more)
▼ The formation of carbon-carbon bonds is of great interest to synthetic chemists because these bonds make up the majority of biologically active compounds. The Mukaiyama aldol reaction is a Lewis-acid-catalyzed carbon-carbon bond-forming reaction that has the ability to produce optically active β-hydroxy carbonyls which can be found in many pharmaceuticals and natural products. Because of precatalyst instability towards hydrolysis, anhydrous solvents are commonly used. Recent efforts have focused on water-tolerant versions of enantioselective Mukaiyama aldol reactions because of the financial and environmental benefits of using aqueous media. Consequently, the Lewis-acidic and water-tolerant features of Ln
3+ ions have aroused great interest in lanthanide-catalyzed bond-forming reactions in aqueous media.
Several Ln
3+-based Lewis acid precatalysts that were designed for Mukaiyama aldol reactions have been shown to be enantioselective, water-tolerant, and recoverable. Limiting the usefulness of these precatalysts are high ligand loadings and long reaction times that are necessary for high enantiomeric ratios. An understanding of water-coordination number, counter anion identitiy, solvent system, and ligand type effect(s) are necessary to improve upon existing Ln
3+-based precatalysts.
I used luminescence-decay measurements and high performance liquid chromatography analyses to study the effects of water-coordination number, counter anion identitiy, and solvent system on reaction rates of Mukaiyama aldol reactions. I found that higher water-coordination numbers and higher water compositions gave rise to more reactive precatalysts for Mukaiyama aldol reactions that were catalyzed by Eu
3+. I synthesized and characterized four new hexadentate ligands to study the effects of ligand type on reactivity and selectivity of Eu
3+-based precatalysts for Mukaiyama aldol reactions. I used Eu
3+ emission spectra and
1H-NMR experiments to study changes in Eu
3+ coordination while titrating hexadentate ligands into solutions of Eu
3+ and I found that Eu
3+ is able to be coordinatively saturated in the presence of excess hexadentate ligands.
By studying Eu
3+ in the presence of different anions and several chiral hexadentate ligands that contain ester, carboxylic acid, alcohol and amide donating groups I was able to find trends in reactivity and selectivity. In this thesis I describe the results that are likely to contribute to the development of highly reactive and selective Ln
3+-based precatalysts.
Advisors/Committee Members: Matthew J. Allen.
Subjects/Keywords: Aqueous; Asymmetric; Catalysis; Europium; Lanthanide; Mukaiyama; Chemistry
Record Details
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APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
Averill, D. J. (2014). Lanthanide-Based Precatalysts For Carbon-Carbon Bond-Forming Reactions In Aqueous Media. (Doctoral Dissertation). Wayne State University. Retrieved from https://digitalcommons.wayne.edu/oa_dissertations/1084
Chicago Manual of Style (16th Edition):
Averill, Derek James. “Lanthanide-Based Precatalysts For Carbon-Carbon Bond-Forming Reactions In Aqueous Media.” 2014. Doctoral Dissertation, Wayne State University. Accessed October 18, 2019.
https://digitalcommons.wayne.edu/oa_dissertations/1084.
MLA Handbook (7th Edition):
Averill, Derek James. “Lanthanide-Based Precatalysts For Carbon-Carbon Bond-Forming Reactions In Aqueous Media.” 2014. Web. 18 Oct 2019.
Vancouver:
Averill DJ. Lanthanide-Based Precatalysts For Carbon-Carbon Bond-Forming Reactions In Aqueous Media. [Internet] [Doctoral dissertation]. Wayne State University; 2014. [cited 2019 Oct 18].
Available from: https://digitalcommons.wayne.edu/oa_dissertations/1084.
Council of Science Editors:
Averill DJ. Lanthanide-Based Precatalysts For Carbon-Carbon Bond-Forming Reactions In Aqueous Media. [Doctoral Dissertation]. Wayne State University; 2014. Available from: https://digitalcommons.wayne.edu/oa_dissertations/1084
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Open Access Theses and Dissertations