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Universiteit Utrecht

1. Bruijnincx, P.C.A. Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif.

Degree: 2007, Universiteit Utrecht

The structural and functional modeling of a specific group of non-heme iron enzymes by the synthesis of small synthetic analogues is the topic of this thesis. The group of non-heme iron enzymes with the 2-His-1-carboxylate facial triad has recently been established as a common platform for the activation of dioxygen in Nature. The oxidative transformations catalyzed by these enzymes are very diverse and many of them are unprecedented in synthetic organic chemistry. This makes this group of enzymes an attractive target for synthetic modeling studies. A new family of biomimetic N,N,O ligands that accurate model this facial triad has been developed. Structurally characterized copper complexes showed the potential of the new ligands as mimics of the facial triad. Mononuclear iron complexes of these ligands were also synthesized and in this way accurate models of the active sites of these enzymes were obtained. For instance, model complexes of the enzyme-substrate complexes of extradiol cleaving catechol dioxygenases were built and the reactivity of these complexes showed that the compounds were able to mimic the enzymes both in structure and function. Very accurate models of the closely related intradiol cleaving catechol dioxygenases were also synthesized with a slightly modified ligand system. These studies provided further insight into the factors governing the respective selectivities of these interesting enzymes. Furthermore, the reactivity of several non-heme iron complexes as oxidation catalysts was explored. Non-heme iron model complexes of the 2-His-1-carboxylate facial triad structural motif proved to be interesting oxidation catalysts and displayed both epoxidation as well as cis-dihydroxylation activity. Other catalysts showed promising reactivities in the oxidation of alkanes and alkenes. All complexes were characterized by variety of techniques including UV-Vis, IR, EPR spectroscopy, magnetic and mass spectrometric measurements, and X-ray crystal structure determinations. In the last part of the thesis, the focus is shifted to the exploration of the coordination of the new ligands with the transitions metals zinc and copper. The obtained results show that the ligands are quite versatile and interesting reactivities were discovered. The zinc complexes for instance mediate the conversion of pyruvate, an important metabolic junction, to oxalate. The copper complexes converted tetrachlorocatechol, a persistent organic pollutant, to chloranilic acid via an oxidative double dehalogenation. Both of these discovered reactivities are unprecedented.

Subjects/Keywords: Scheikunde; bioinorganic chemistry; non-heme iron enzymes; 2-His-1-carboxylate facial triad; N,N,O ligands; small synthetic analogues; oxidation catalysis; epoxidation; cis-dihydroxylation; copper; zinc

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

APA (6th Edition):

Bruijnincx, P. C. A. (2007). Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif. (Doctoral Dissertation). Universiteit Utrecht. Retrieved from http://dspace.library.uu.nl:8080/handle/1874/19232

Chicago Manual of Style (16th Edition):

Bruijnincx, P C A. “Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif.” 2007. Doctoral Dissertation, Universiteit Utrecht. Accessed December 06, 2019. http://dspace.library.uu.nl:8080/handle/1874/19232.

MLA Handbook (7th Edition):

Bruijnincx, P C A. “Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif.” 2007. Web. 06 Dec 2019.

Vancouver:

Bruijnincx PCA. Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif. [Internet] [Doctoral dissertation]. Universiteit Utrecht; 2007. [cited 2019 Dec 06]. Available from: http://dspace.library.uu.nl:8080/handle/1874/19232.

Council of Science Editors:

Bruijnincx PCA. Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif. [Doctoral Dissertation]. Universiteit Utrecht; 2007. Available from: http://dspace.library.uu.nl:8080/handle/1874/19232

2. Bruijnincx, P.C.A. Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif.

Degree: 2007, University Utrecht

The structural and functional modeling of a specific group of non-heme iron enzymes by the synthesis of small synthetic analogues is the topic of this thesis. The group of non-heme iron enzymes with the 2-His-1-carboxylate facial triad has recently been established as a common platform for the activation of dioxygen in Nature. The oxidative transformations catalyzed by these enzymes are very diverse and many of them are unprecedented in synthetic organic chemistry. This makes this group of enzymes an attractive target for synthetic modeling studies. A new family of biomimetic N,N,O ligands that accurate model this facial triad has been developed. Structurally characterized copper complexes showed the potential of the new ligands as mimics of the facial triad. Mononuclear iron complexes of these ligands were also synthesized and in this way accurate models of the active sites of these enzymes were obtained. For instance, model complexes of the enzyme-substrate complexes of extradiol cleaving catechol dioxygenases were built and the reactivity of these complexes showed that the compounds were able to mimic the enzymes both in structure and function. Very accurate models of the closely related intradiol cleaving catechol dioxygenases were also synthesized with a slightly modified ligand system. These studies provided further insight into the factors governing the respective selectivities of these interesting enzymes. Furthermore, the reactivity of several non-heme iron complexes as oxidation catalysts was explored. Non-heme iron model complexes of the 2-His-1-carboxylate facial triad structural motif proved to be interesting oxidation catalysts and displayed both epoxidation as well as cis-dihydroxylation activity. Other catalysts showed promising reactivities in the oxidation of alkanes and alkenes. All complexes were characterized by variety of techniques including UV-Vis, IR, EPR spectroscopy, magnetic and mass spectrometric measurements, and X-ray crystal structure determinations. In the last part of the thesis, the focus is shifted to the exploration of the coordination of the new ligands with the transitions metals zinc and copper. The obtained results show that the ligands are quite versatile and interesting reactivities were discovered. The zinc complexes for instance mediate the conversion of pyruvate, an important metabolic junction, to oxalate. The copper complexes converted tetrachlorocatechol, a persistent organic pollutant, to chloranilic acid via an oxidative double dehalogenation. Both of these discovered reactivities are unprecedented.

Subjects/Keywords: bioinorganic chemistry; non-heme iron enzymes; 2-His-1-carboxylate facial triad; N,N,O ligands; small synthetic analogues; oxidation catalysis; epoxidation; cis-dihydroxylation; copper; zinc

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

APA (6th Edition):

Bruijnincx, P. C. A. (2007). Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif. (Doctoral Dissertation). University Utrecht. Retrieved from http://dspace.library.uu.nl/handle/1874/19232 ; URN:NBN:NL:UI:10-1874-19232 ; urn:isbn:978-90-393-4438-5 ; URN:NBN:NL:UI:10-1874-19232 ; http://dspace.library.uu.nl/handle/1874/19232

Chicago Manual of Style (16th Edition):

Bruijnincx, P C A. “Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif.” 2007. Doctoral Dissertation, University Utrecht. Accessed December 06, 2019. http://dspace.library.uu.nl/handle/1874/19232 ; URN:NBN:NL:UI:10-1874-19232 ; urn:isbn:978-90-393-4438-5 ; URN:NBN:NL:UI:10-1874-19232 ; http://dspace.library.uu.nl/handle/1874/19232.

MLA Handbook (7th Edition):

Bruijnincx, P C A. “Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif.” 2007. Web. 06 Dec 2019.

Vancouver:

Bruijnincx PCA. Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif. [Internet] [Doctoral dissertation]. University Utrecht; 2007. [cited 2019 Dec 06]. Available from: http://dspace.library.uu.nl/handle/1874/19232 ; URN:NBN:NL:UI:10-1874-19232 ; urn:isbn:978-90-393-4438-5 ; URN:NBN:NL:UI:10-1874-19232 ; http://dspace.library.uu.nl/handle/1874/19232.

Council of Science Editors:

Bruijnincx PCA. Structural and Functional Models of Non-Heme Iron Enzymes : A Study of the 2-His-1-Carboxylate Facial Triad Structural Motif. [Doctoral Dissertation]. University Utrecht; 2007. Available from: http://dspace.library.uu.nl/handle/1874/19232 ; URN:NBN:NL:UI:10-1874-19232 ; urn:isbn:978-90-393-4438-5 ; URN:NBN:NL:UI:10-1874-19232 ; http://dspace.library.uu.nl/handle/1874/19232

3. Prat Casellas, Irene. Bioinspired non-heme iron catalysts for challenging oxidative transformations: mechanistic studies and catalytic applications on selective alkane hydroxylation and alkene cis-dihydroxilation.

Degree: Departament de Química, 2013, Universitat de Girona

La funcionalització d'hidrocarburs de manera sostenible i eficaç és un dels principals reptes per la química moderna, degut a que la seva abundància natural els fa una important matèria primera. L'oxidació d'hidrocarburs és una de les reaccions més interessants, ja que la introducció d’un àtom d’oxigen en l’estructura d’un hidrocarburs li confereix funcionalitat química, fa augmentar el seu valor i els converteix en reactius adients per subseqüents transformacions químiques. No obstant això, aquestes reaccions són difícils a causa de la inherent baixa reactivitat dels hidrocarburs. Les metodologies actualment disponibles impliquen la utilització d’espècies altament oxidants i tòxiques, altes temperatures i llargs temps de reacció per tal de superar aquesta manca de reactivitat. Aquestes condicions extremes eviten que la química es pugui dur a terme de manera selectiva, fet essencial per produir productes d’alt valor sintètic. Un avanç important és el desenvolupament de metodologies de reacció suaus que permetin l'oxidació d'enllaços C-H i C=C amb alta regio- i estereoselectivitat. Els sistemes naturals, com ara enzims de ferro, són capaços de realitzar aquesta química. El ferro és l’element metàl•lic més abundant a la terra i és clau per nombrosos processos vitals, a més la seva baixa toxicitat el fa un atractiu material per substituir els elements de segona i tercera seria de transició més cars i tòxics emprats actualment. Un dels principals objectius d’aquesta tesi és dissenyar catalitzadors de ferro que imiten l’estructura i la funció dels enzims naturals per tal de trobar una nova metodologia que permeti l'oxidació selectiva d'enllaços C-H i C=C utilitzant condicions suaus i mediambientalment més benignes que les metodologies tradicionals. A més, l’estudi d’aquests sistemes pot donar informació útil sobre el mecanisme d’oxidació del propi enzim. Els resultats obtinguts en aquesta tesi aclareixen el mecanisme pel qual es duu a terme la hidroxilació de l’enllaç C-H amb retenció de la estereoselectivitat en centres mononuclears de ferro, i evidencien la formació d’una espècie de ferro (V) d’alt estat d’oxidació capaç de catalitzar la cis-dihidroxilació d’alquens. A més a més, es descobreix un catalitzador eficient i selectiu capaç de dur a terme aquesta química en condicions d’escala preparativa Advisors/Committee Members: [email protected] (authoremail), false (authoremailshow), Costas Salgueiro, Miquel (director), Ribas Salamaña, Xavi (director), true (authorsendemail).

Subjects/Keywords: Iron catalysts; Catalitzadors de ferro; Catalizadores de hierro; C-H oxidation; Oxidació C-H; Oxidación C-H; Hidrogen peroxide; Peròxid d'hidrògen; Peróxido de hidrógeno; cis-dihydroxylation; cis-dihidroxilació; cis-dihidroxilación; Bioinspired catalysis; Catalitzadors bioinspirats; Catalizadores bioinspirados; Homogeneous catalysis; Catalitzadors homogenis; Catalizadores homogéneos; 546

…p. 113). Chapter VI. Fe(Pytacn)-catalyzed cis-dihydroxylation of olefins… …37 I.3.2.2. cis-Dihydroxylation… …113 CHAPTER VI. FE(PYTACN)-CATALYZED CIS-DIHYDROXYLATION OF OLEFINS WITH HYDROGEN… …158 VIII.4. Fe(Pytacn)-catalyzed cis-dihydroxylation of olefins with hydrogen… …165 VIII.4.2. cis-Dihydroxylation mechanism… 

Record DetailsSimilar RecordsGoogle PlusoneFacebookTwitterCiteULikeMendeleyreddit

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

APA (6th Edition):

Prat Casellas, I. (2013). Bioinspired non-heme iron catalysts for challenging oxidative transformations: mechanistic studies and catalytic applications on selective alkane hydroxylation and alkene cis-dihydroxilation. (Thesis). Universitat de Girona. Retrieved from http://hdl.handle.net/10803/117778

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):

Prat Casellas, Irene. “Bioinspired non-heme iron catalysts for challenging oxidative transformations: mechanistic studies and catalytic applications on selective alkane hydroxylation and alkene cis-dihydroxilation.” 2013. Thesis, Universitat de Girona. Accessed December 06, 2019. http://hdl.handle.net/10803/117778.

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

MLA Handbook (7th Edition):

Prat Casellas, Irene. “Bioinspired non-heme iron catalysts for challenging oxidative transformations: mechanistic studies and catalytic applications on selective alkane hydroxylation and alkene cis-dihydroxilation.” 2013. Web. 06 Dec 2019.

Vancouver:

Prat Casellas I. Bioinspired non-heme iron catalysts for challenging oxidative transformations: mechanistic studies and catalytic applications on selective alkane hydroxylation and alkene cis-dihydroxilation. [Internet] [Thesis]. Universitat de Girona; 2013. [cited 2019 Dec 06]. Available from: http://hdl.handle.net/10803/117778.

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

Council of Science Editors:

Prat Casellas I. Bioinspired non-heme iron catalysts for challenging oxidative transformations: mechanistic studies and catalytic applications on selective alkane hydroxylation and alkene cis-dihydroxilation. [Thesis]. Universitat de Girona; 2013. Available from: http://hdl.handle.net/10803/117778

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

.