401
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Nestl B, Kroutil W, Faber K. Biocatalytic Racemization of α-Hydroxy Ketones (Acyloins) at Physiological Conditions usingLactobacillus paracasei DSM 20207. Adv Synth Catal 2006. [DOI: 10.1002/adsc.200606055] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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402
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Akai S, Tanimoto K, Kanao Y, Egi M, Yamamoto T, Kita Y. A Dynamic Kinetic Resolution of Allyl Alcohols by the Combined Use of Lipases and [VO(OSiPh3)3]. Angew Chem Int Ed Engl 2006; 45:2592-5. [PMID: 16544360 DOI: 10.1002/anie.200503765] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Shuji Akai
- School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8526, Japan.
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403
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Akai S, Tanimoto K, Kanao Y, Egi M, Yamamoto T, Kita Y. A Dynamic Kinetic Resolution of Allyl Alcohols by the Combined Use of Lipases and [VO(OSiPh3)3]. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503765] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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404
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Zimmermann V, Beller M, Kragl U. Modelling the Reaction Course of a Dynamic Kinetic Resolution of Amino Acid Derivatives: Identifying and Overcoming Bottlenecks. Org Process Res Dev 2006. [DOI: 10.1021/op0502349] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Vera Zimmermann
- Universität Rostock, Abteilung für Analytische, Technische und Umweltchemie, Albert-Einstein-Strasse 3a, 18059 Rostock, Germany, and Leibniz-Institut für Katalyse an der Universität Rostock e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
| | - Matthias Beller
- Universität Rostock, Abteilung für Analytische, Technische und Umweltchemie, Albert-Einstein-Strasse 3a, 18059 Rostock, Germany, and Leibniz-Institut für Katalyse an der Universität Rostock e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
| | - Udo Kragl
- Universität Rostock, Abteilung für Analytische, Technische und Umweltchemie, Albert-Einstein-Strasse 3a, 18059 Rostock, Germany, and Leibniz-Institut für Katalyse an der Universität Rostock e.V., Albert-Einstein-Strasse 29a, 18059 Rostock, Germany
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405
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Fransson ABL, Xu Y, Leijondahl K, Bäckvall JE. Enzymatic Resolution, Desymmetrization, and Dynamic Kinetic Asymmetric Transformation of 1,3-Cycloalkanediols. J Org Chem 2006; 71:6309-16. [PMID: 16901110 DOI: 10.1021/jo060002n] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An efficient desymmetrization of cis-1,3-cyclohexanediol to (1S,3R)-3-(acetoxy)-1-cyclohexanol ((R,S)-2a) was performed via Candida antarctica lipase B (CALB)-catalyzed transesterification, in high yield (up to 93%) and excellent enantioselectivity (ee's up to >99.5%). (R,R)-Diacetate ((R,R)-3a) was obtained in a DYKAT process at room temperature from (1S,3R)-3-acetoxy-1-cyclohexanol ((R,S)-2a), in a high trans/cis ratio (91:9) and in excellent enantioselectivity of >99%. Metal- and enzyme-catalyzed dynamic transformation of cis/trans-1,3-cyclohexanediol using PS-C gave a high diastereoselectivity for cis-diacetate (cis/trans = 97:3). The (1R,3S)-3-acetoxy-1-cyclohexanol (ent-(R,S)-2a) was obtained from cis-diacetate by CALB-catalyzed hydrolysis in an excellent yield (97%) and selectivity (>99% ee). By deuterium labeling it was shown that intramolecular acyl migration does not occur in the transformation of cis-monoacetate to the cis-diacetate.
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Affiliation(s)
- Ann-Britt L Fransson
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
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406
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Biocatalytic approaches for the quantitative production of single stereoisomers from racemates. Biochem Soc Trans 2006. [DOI: 10.1042/bst0340296] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Strategies for the chemoenzymatic transformation of a racemate into a single stereoisomeric product in quantitative yield have been developed. A range of industrially relevant α-hydroxycarboxylic acids was deracemized in a stepwise fashion via lipase-catalysed enantioselective O-acylation, followed by mandelate racemase-catalysed racemization of the remaining non-reacted substrate enantiomer. Alternatively, aliphatic α-hydroxycarboxylic acids were enzymatically isomerized using whole resting cells of Lactobacillus spp. Enantioselective hydrolysis of rac-sec-alkyl sulphate esters was accomplished using novel alkyl sulphatases of microbial origin. The stereochemical path of catalysis could be controlled by choice of the biocatalyst. Whereas Rhodococcus ruber DSM 44541 and Sulfolobus acidocaldarius DSM 639 act through inversion of configuration, stereo-complementary retaining sulphatase activity was detected in the marine planctomycete Rhodopirellula baltica DSM 10527.
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407
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Hilker I, Rabani G, Verzijl GKM, Palmans ARA, Heise A. Chiral Polyesters by Dynamic Kinetic Resolution Polymerization. Angew Chem Int Ed Engl 2006; 45:2130-2. [PMID: 16502440 DOI: 10.1002/anie.200503496] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Iris Hilker
- DSM Research, P.O. Box 18, 6160 MD Geleen, The Netherlands
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408
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Hilker I, Rabani G, Verzijl GKM, Palmans ARA, Heise A. Chirale Polyester durch dynamische kinetische Racematspaltungspolymerisation. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503496] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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409
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van Maarseveen JH, Reek JNH, Back JW. Kovalente Markierung von Proteinen durch Übergangsmetallkatalyse. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200504352] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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410
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van Maarseveen JH, Reek JNH, Back JW. Transition-Metal Catalysis as a Tool for the Covalent Labeling of Proteins. Angew Chem Int Ed Engl 2006; 45:1841-3. [PMID: 16493720 DOI: 10.1002/anie.200504352] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jan H van Maarseveen
- Van't Hoff Institute for Molecular Sciences, University of Amsterdam, The Netherlands.
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411
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Simons C, Hanefeld U, Arends I, Maschmeyer T, Sheldon R. A One-Pot Enantioselective Chemo-Enzymatic Synthesis of Amino Acids in Water. Adv Synth Catal 2006. [DOI: 10.1002/adsc.200505395] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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412
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Rossbach BM, Leopold K, Weberskirch R. Selbstorganisierte Nanoreaktoren als hochaktive Katalysatoren in der hydrolytischen Ringöffnung terminaler Epoxide in Wasser. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200503291] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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413
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Rossbach BM, Leopold K, Weberskirch R. Self-Assembled Nanoreactors as Highly Active Catalysts in the Hydrolytic Kinetic Resolution (HKR) of Epoxides in Water. Angew Chem Int Ed Engl 2006; 45:1309-12. [PMID: 16425317 DOI: 10.1002/anie.200503291] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Benjamin M Rossbach
- Department Chemie, Lehrstuhl für Makromolekulare Stoffe, Technische Universität München, Lichtenbergstrasse 4, 85747 Garching, Germany
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414
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Markowicz SW, Figlus M, Lejkowski M, Karolak-Wojciechowska J, Dzierżawska-Majewska A, Verpoort F. Enantiomerically pure α-pinene derivatives from material of 65% enantiomeric purity. Part 2: C2-symmetric N,N′-3-(2α-hydroxy)pinane diimines and diamines. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.tetasy.2006.01.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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415
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416
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van Buijtenen J, Meuldijk J, Vekemans JAJM, Hulshof LA, Kooijman H, Spek AL. Dinuclear Ruthenium Complexes Bearing Dicarboxylate and Phosphine Ligands. Acceptorless Catalytic Dehydrogenation of 1-Phenylethanol. Organometallics 2006. [DOI: 10.1021/om050789s] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jeroen van Buijtenen
- Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Process Development Group, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Bijvoet Center for Biomolecular Research, Crystal and Structural Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Jan Meuldijk
- Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Process Development Group, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Bijvoet Center for Biomolecular Research, Crystal and Structural Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Jef A. J. M. Vekemans
- Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Process Development Group, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Bijvoet Center for Biomolecular Research, Crystal and Structural Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Lumbertus A. Hulshof
- Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Process Development Group, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Bijvoet Center for Biomolecular Research, Crystal and Structural Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Huub Kooijman
- Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Process Development Group, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Bijvoet Center for Biomolecular Research, Crystal and Structural Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Anthony L. Spek
- Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Process Development Group, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven, The Netherlands, Bijvoet Center for Biomolecular Research, Crystal and Structural Chemistry, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
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417
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Borén L, Martín-Matute B, Xu Y, Córdova A, Bäckvall JE. (S)-Selective Kinetic Resolution and Chemoenzymatic Dynamic Kinetic Resolution of Secondary Alcohols. Chemistry 2006; 12:225-32. [PMID: 16267860 DOI: 10.1002/chem.200500758] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
(S)-Selective kinetic resolution was achieved through the use of a commercially available protease, which was activated with a combination of two different surfactants. The kinetic resolution (KR) process was optimized with respect to activation of the protease and to the acyl donor. The KR proved to be compatible with a range of functionalized sec-alcohols, giving good to high enantiomeric ratio values (up to >200). The enzymatic resolution was combined with a ruthenium-catalyzed racemization to give an (S)-selective dynamic kinetic resolution (DKR) of sec-alcohols. The DKR process works under very mild reaction conditions to give the corresponding esters in high yields and with excellent enantioselectivities.
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Affiliation(s)
- Linnéa Borén
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 106 91 Stockholm, Sweden
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418
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Fogassy E, Nógrádi M, Kozma D, Egri G, Pálovics E, Kiss V. Optical resolution methods. Org Biomol Chem 2006; 4:3011-30. [PMID: 16886066 DOI: 10.1039/b603058k] [Citation(s) in RCA: 160] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Despite the large number of elaborate enantioselective syntheses for the preparation of a single enantiomer to achieve industrial and scientific goals, the separation and purification of enantiomers (components of racemic compounds) is also necessary. Hence, we present the most often used thought-provoking modern methods based on momentous recognitions (e.g. spontaneous resolution, induced crystallization, resolution by formation of diastereomers, resolution by formation of non-covalent diastereomers, resolution by diastereomeric salt formation, resolution by diastereomeric complex formation, "half equivalent" methods of resolution, separation by crystallization, separation by distillation, separation by supercritical fluid extraction, resolution with mixtures of resolving agents, resolution with a derivative of the target compound, enantioselective chromatography, resolution by formation of covalent diastereomers, resolution by substrate selective reaction, kinetic resolution without enzymes, kinetic resolution by enzyme catalysis, hydrolytic and redox enzymes, kinetic and thermodynamic control, resolutions combined with 2nd order asymmetric transformations, enrichment of partially resolved mixtures, role of the solvent and methods of optimization in the separation of diastereoisomers, non-linear effects and selected examples of resolution on an industrial scale).
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Affiliation(s)
- Elemér Fogassy
- Institute of Organic Chemical Technology, University of Technology and Economics, Budapest, POB 91, Hungary
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419
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Samec JSM, Bäckvall JE, Andersson PG, Brandt P. Mechanistic aspects of transition metal-catalyzed hydrogen transfer reactions. Chem Soc Rev 2006; 35:237-48. [PMID: 16505918 DOI: 10.1039/b515269k] [Citation(s) in RCA: 890] [Impact Index Per Article: 49.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this tutorial review recent mechanistic studies on transition metal-catalyzed hydrogen transfer reactions are discussed. A common feature of these reactions is that they involve metal hydrides, which may be monohydrides or dihydrides. An important question is whether the substrate coordinates to the metal (inner-sphere hydrogen transfer) or if there is a direct concerted transfer of hydrogen from the metal to substrate (outer-sphere hydrogen transfer). Both experimental and theoretical studies are reviewed.
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Affiliation(s)
- Joseph S M Samec
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
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420
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Directed Evolution of Enantioselective Enzymes as Catalysts for Organic Synthesis. ADVANCES IN CATALYSIS 2006. [DOI: 10.1016/s0360-0564(05)49001-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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421
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van Buijtenen J, van As BAC, Meuldijk J, Palmans ARA, Vekemans JAJM, Hulshof LA, Meijer EW. Chiral polymers by iterative tandem catalysis. Chem Commun (Camb) 2006:3169-71. [PMID: 17028732 DOI: 10.1039/b606241e] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Racemic omega-substituted caprolactones can be completely converted into chiral polyesters of remarkable MW and high ee by combining lipase-catalyzed ring-opening polymerization with Ru-catalyzed racemization.
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Affiliation(s)
- Jeroen van Buijtenen
- Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, P. O. Box 513, 5600 MB Eindhoven, The Netherlands
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422
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Gladiali S, Alberico E. Asymmetric transfer hydrogenation: chiral ligands and applications. Chem Soc Rev 2005; 35:226-36. [PMID: 16505917 DOI: 10.1039/b513396c] [Citation(s) in RCA: 907] [Impact Index Per Article: 47.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Hydrogen transfer reduction processes are attracting increasing interest from synthetic chemists in view of their operational simplicity and high selectivity. In this tutorial review the most significant advances recently achieved in the stereoselective reduction of unsaturated organic compounds catalyzed by homogeneous transition metal complexes are critically reviewed. A sharp growth of the synthetic applications of this technique in the synthesis of fine chemicals is predictable as the use of transition metal catalyzed reactions will become more familiar to synthetic chemists.
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Affiliation(s)
- Serafino Gladiali
- Dipartimento di Chimica, Università di Sassari, Via Vienna 2, 07100 Sassari, Italy.
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423
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Bornscheuer UT. Trends and challenges in enzyme technology. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2005; 100:181-203. [PMID: 16270658 DOI: 10.1007/b136413] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
Several major developments took place in the field of biocatalysis over the past few years. These include the invention of directed evolution as an extremely useful method for biocatalyst improvement on the molecular level in combination with high-throughput screening systems, methods for accessing "nonculturable" biodiversity using metagenome approaches and progress in sequence-based biocatalyst discovery. In addition, new carriers and tools for immobilization of enzymes have been developed. For the synthesis of optically active compounds impressive examples using new enzymes and major progress in dynamic kinetic resolutions of racemates took place. These achievements are summarized in this review.
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Affiliation(s)
- Uwe T Bornscheuer
- Department of Technical Chemistry and Biotechnology, Institute of Chemistry and Biochemistry, Greifswald University, Soldmannstr. 16, 17487 Greifswald, Germany.
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424
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Yamaguchi K, Koike T, Kotani M, Matsushita M, Shinachi S, Mizuno N. Synthetic Scope and Mechanistic Studies of Ru(OH)x/Al2O3-Catalyzed Heterogeneous Hydrogen-Transfer Reactions. Chemistry 2005; 11:6574-82. [PMID: 16092142 DOI: 10.1002/chem.200500539] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Three kinds of hydrogen-transfer reactions, namely racemization of chiral secondary alcohols, reduction of carbonyl compounds to alcohols using 2-propanol as a hydrogen donor, and isomerization of allylic alcohols to saturated ketones, are efficiently promoted by the easily prepared and inexpensive supported ruthenium catalyst Ru(OH)x/Al2O3. A wide variety of substrates, such as aromatic, aliphatic, and heterocyclic alcohols or carbonyl compounds, can be converted into the desired products, under anaerobic conditions, in moderate to excellent yields and without the need for additives such as bases. A larger scale, solvent-free reaction is also demonstrated: the isomerization of 1-octen-3-ol with a substrate/catalyst ratio of 20,000/1 shows a very high turnover frequency (TOF) of 18,400 h(-1), with a turnover number (TON) that reaches 17,200. The catalysis for these reactions is intrinsically heterogeneous in nature, and the Ru(OH)x/Al2O3 recovered after the reactions can be reused without appreciable loss of catalytic performance. The reaction mechanism of the present Ru(OH)x/Al2O3-catalyzed hydrogen-transfer reactions were examined with monodeuterated substrates. After the racemization of (S)-1-deuterio-1-phenylethanol in the presence of acetophenone was complete, the deuterium content at the alpha-position of the corresponding racemic alcohol was 91%, whereas no deuterium was incorporated into the alpha-position during the racemization of (S)-1-phenylethanol-OD. These results show that direct carbon-to-carbon hydrogen transfer occurs via a metal monohydride for the racemization of chiral secondary alcohols and reduction of carbonyl compounds to alcohols. For the isomerization, the alpha-deuterium of 3-deuterio-1-octen-3-ol was selectively relocated at the beta-position of the corresponding ketones (99% D at the beta-position), suggesting the involvement of a 1,4-addition of ruthenium monohydride species to the alpha,beta-unsaturated ketone intermediate. The ruthenium monohydride species and the alpha,beta-unsaturated ketone would be formed through alcoholate formation/beta-elimination. Kinetic studies and kinetic isotope effects show that the Ru-H bond cleavage (hydride transfer) is included in the rate-determining step.
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Affiliation(s)
- Kazuya Yamaguchi
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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425
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Anderson NG. Developing Processes for Crystallization-Induced Asymmetric Transformation. Org Process Res Dev 2005. [DOI: 10.1021/op050119y] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Neal G. Anderson
- Anderson's Process Solutions, 7400 Griffin Lane, Jacksonville, Oregon 97530, U.S.A
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426
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Gouverneur V, Reiter M. Biocatalytic Approaches to Hetero-Diels-Alder Adducts of Carbonyl Compounds. Chemistry 2005; 11:5806-15. [PMID: 16003810 DOI: 10.1002/chem.200500406] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Very little information is available on hetero-Diels-Alderases for the assembly of heterocyclic products despite the synthetic value of these [4+2] cycloadditions. Hetero-Diels-Alderase antibodies raised against a bicyclic transition state analogue have been generated for the cycloaddition of ethylglyoxylate with an all-carbon diene. More recently, a conceptually novel biocatalytic approach to hetero-Diels-Alder (HDA) adducts derived from carbonyl dienophiles has been developed mirroring a stepwise aldol Michael mechanism instead of a concerted pathway. In this approach, the two key steps are an antibody-mediated kinetic resolution of beta-hydroxyenones and a subsequent ring-closure process. An attractive feature of this methodology is the possibility to convert the enantioenriched aldol intermediates into tetrahydropyranones or dihydropyranones. This bioorganic route is best applied for the preparation of enantioenriched HDA adducts derived from poorly electrophilic acceptors, therefore complementing existing catalytic routes to these adducts based on the use of small organocatalysts or chiral Lewis acids.
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Affiliation(s)
- Véronique Gouverneur
- University of Oxford, Chemistry Research Laboratory, 12 Mansfield Road, OX1 3TA Oxford, UK.
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427
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Palladium-catalyzed asymmetric synthesis of allylic alcohols from unsymmetrical and symmetrical racemic allylic carbonates featuring C–O-bond formation and dynamic kinetic resolution. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.07.044] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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428
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Kim N, Ko SB, Kwon MS, Kim MJ, Park J. Air-Stable Racemization Catalyst for Dynamic Kinetic Resolution of Secondary Alcohols at Room Temperature. Org Lett 2005; 7:4523-6. [PMID: 16178574 DOI: 10.1021/ol051889x] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] A novel racemization catalyst was synthesized for the dynamic kinetic resolution (DKR) of alcohols with a lipase at room temperature in the air. Furthermore, a polymer-supported derivative was also synthesized and tested as a recyclable catalyst for the aerobic DKR of alcohols.
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Affiliation(s)
- Namdu Kim
- National Research Laboratory of Chirotechnology, Department of Chemistry, Division of Molecular and Life Sciences, Pohang University of Science and Technology (POSTECH), San 31 Hyojadong, Pohang 790-784, Korea
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429
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van As BAC, van Buijtenen J, Heise A, Broxterman QB, Verzijl GKM, Palmans ARA, Meijer EW. Chiral Oligomers by Iterative Tandem Catalysis. J Am Chem Soc 2005; 127:9964-5. [PMID: 16011336 DOI: 10.1021/ja052347d] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Iterative tandem catalysis is presented as a flexible tool for obtaining chiral macromolecules from racemic or prochiral monomers. Here, we combine lipase-catalyzed ring-opening of omega-substituted lactones with ruthenium-catalyzed racemization. In a two-pot system, enantioenriched oligomers of 6-methyl-epsilon-caprolactone were synthesized, which could not have been obtained by enzymatic ring-opening alone. A one-pot experiment proved highly promising in developing a novel route toward enantiopure polyesters.
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Affiliation(s)
- Bart A C van As
- Laboratory of Macromolecular and Organic Chemistry, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands
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430
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Samec JS, Mony L, Bäckvall JE. Efficient ruthenium catalyzed transfer hydrogenation of functionalized imines by isopropanol under controlled microwave heating. CAN J CHEM 2005. [DOI: 10.1139/v05-103] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Transfer hydrogenation of various functionalized imines by isopropanol catalyzed by [Ru(CO)2(Ph4C4CO)]2 (3) has been studied. The use of either an oil bath or controlled microwave heating in toluene led to an efficient procedure with high turnover frequencies and the product amines were obtained in high yields. An advantage with catalyst 3 over the conventional [Ru2(CO)4(µ-H)(Ph4C4COHOCC4Ph4)] (1) is the absence of an initiation period, which results in a faster reaction with 3 as compared to 1.Key words: transfer hydrogenation, ruthenium, imines, microwave.
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431
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Martín-Matute B, Edin M, Bogár K, Kaynak FB, Bäckvall JE. Combined Ruthenium(II) and Lipase Catalysis for Efficient Dynamic Kinetic Resolution of Secondary Alcohols. Insight into the Racemization Mechanism. J Am Chem Soc 2005; 127:8817-25. [PMID: 15954789 DOI: 10.1021/ja051576x] [Citation(s) in RCA: 258] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pentaphenylcyclopentadienyl ruthenium complexes (3) are excellent catalysts for the racemization of secondary alcohols at ambient temperature. The combination of this process with enzymatic resolution of the alcohols results in a highly efficient synthesis of enantiomerically pure acetates at room temperature with short reaction times for most substrates. This new reaction was applied to a wide range of functionalized alcohols including heteroaromatic alcohols, and for many of the latter, enantiopure acetates were efficiently prepared for the first time via dynamic kinetic resolution (DKR). Different substituted cyclopentadienyl ruthenium complexes were prepared and studied as catalysts for racemization of alcohols. Pentaaryl-substituted cyclopentadienyl complexes were found to be highly efficient catalysts for the racemization. Substitution of one of the aryl groups by an alkyl group considerably slows down the racemization process. A study of the racemization of (S)-1-phenylethanol catalyzed by ruthenium hydride eta(5)-Ph(5)CpRu(CO)(2)H (8) indicates that the racemization takes place within the coordination sphere of the ruthenium catalyst. This conclusion was supported by the lack of ketone exchange in the racemization of (S)-1-phenylethanol performed in the presence of p-tolyl methyl ketone (1 equiv), which gave <1% of 1-(p-tolyl)ethanol. The structures of ruthenium chloride and iodide complexes 3a and 3c and of ruthenium hydride complex 8 were confirmed by X-ray analysis.
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Affiliation(s)
- Belén Martín-Matute
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
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432
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Affiliation(s)
- Julia-Christina Wasilke
- Department of Chemistry and Biochemistry, Institute for Polymers and Organic Solids, University of California, Santa Barbara, California 93106, USA
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433
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434
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Glueck SM, Pirker M, Nestl BM, Ueberbacher BT, Larissegger-Schnell B, Csar K, Hauer B, Stuermer R, Kroutil W, Faber K. Biocatalytic Racemization of Aliphatic, Arylaliphatic, and Aromatic α-Hydroxycarboxylic Acids. J Org Chem 2005; 70:4028-32. [PMID: 15876092 DOI: 10.1021/jo050156n] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Biocatalytic racemization of a range of aliphatic, (aryl)aliphatic, and aromatic alpha-hydroxycarboxylic acids was accomplished by using whole resting cells of a range of Lactobacillus spp. The mild (physiological) reaction conditions ensured an essentially "clean" isomerization in the absence of side reactions, such as elimination or decomposition. Whereas straight-chain aliphatic 2-hydroxycarboxylic acids were racemized with excellent rates (up to 85% relative to lactate), steric hindrance was observed for branched-chain analogues. Good rates were observed for aryl-alkyl derivatives, such as 3-phenyllactic acid (up to 59%) and 4-phenyl-2-hydroxybutanoic acid (up to 47%). In addition, also mandelate and its o-chloro analogue were accepted at a fair rate (45%). This biocatalytic racemization represents an important tool for the deracemization of a number of pharmaceutically important building blocks.
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Affiliation(s)
- Silvia M Glueck
- Department of Chemistry, Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria
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435
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Verzijl GK, de Vries JG, Broxterman QB. Removal of the acyl donor residue allows the use of simple alkyl esters as acyl donors for the dynamic kinetic resolution of secondary alcohols. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.tetasy.2005.02.028] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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436
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Dynamic Kinetic Resolutions and Asymmetric Transformations by Enzyme-Metal Combo Catalysis. B KOREAN CHEM SOC 2005. [DOI: 10.5012/bkcs.2005.26.4.515] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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437
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Xu K, Lalic G, Sheehan SM, Shair MD. Dynamic Kinetic Resolution during a Cascade Reaction on Substrates with Chiral All-Carbon Quaternary Centers. Angew Chem Int Ed Engl 2005; 44:2259-61. [PMID: 15751105 DOI: 10.1002/anie.200462039] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Kaichen Xu
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA 02138, USA
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438
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Kourist R, González-Sabín J, Liz R, Rebolledo F. Kinetic Resolution of 1-Biaryl- and 1-(Pyridylphenyl)alkan-1-ols Catalysed by the Lipase B fromCandida antarctica. Adv Synth Catal 2005. [DOI: 10.1002/adsc.200404330] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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439
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Xu K, Lalic G, Sheehan SM, Shair MD. Dynamic Kinetic Resolution during a Cascade Reaction on Substrates with Chiral All-Carbon Quaternary Centers. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200462039] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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440
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Letondor C, Humbert N, Ward TR. Artificial metalloenzymes based on biotin-avidin technology for the enantioselective reduction of ketones by transfer hydrogenation. Proc Natl Acad Sci U S A 2005; 102:4683-7. [PMID: 15772162 PMCID: PMC555699 DOI: 10.1073/pnas.0409684102] [Citation(s) in RCA: 169] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2004] [Indexed: 11/18/2022] Open
Abstract
Most physiological and biotechnological processes rely on molecular recognition between chiral (handed) molecules. Manmade homogeneous catalysts and enzymes offer complementary means for producing enantiopure (single-handed) compounds. As the subtle details that govern chiral discrimination are difficult to predict, improving the performance of such catalysts often relies on trial-and-error procedures. Homogeneous catalysts are optimized by chemical modification of the chiral environment around the metal center. Enzymes can be improved by modification of gene encoding the protein. Incorporation of a biotinylated organometallic catalyst into a host protein (avidin or streptavidin) affords versatile artificial metalloenzymes for the reduction of ketones by transfer hydrogenation. The boric acid.formate mixture was identified as a hydrogen source compatible with these artificial metalloenzymes. A combined chemo-genetic procedure allows us to optimize the activity and selectivity of these hybrid catalysts: up to 94% (R) enantiomeric excess for the reduction of p-methylacetophenone. These artificial metalloenzymes display features reminiscent of both homogeneous catalysts and enzymes.
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Affiliation(s)
- Christophe Letondor
- Institute of Chemistry, University of Neuchâtel, Avenue Bellevaux 51, CP 2, CH-2007 Neuchâtel, Switzerland
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441
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García-Urdiales E, Alfonso I, Gotor V. Enantioselective enzymatic desymmetrizations in organic synthesis. Chem Rev 2005; 105:313-54. [PMID: 15720156 DOI: 10.1021/cr040640a] [Citation(s) in RCA: 396] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Eduardo García-Urdiales
- Departamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, Julián Clavería, 8, 33071 Oviedo, Spain
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442
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Medici S, Gagliardo M, Williams S, Chase P, Gladiali S, Lutz M, Spek A, van?Klink G, van?Koten G. Novel P-Stereogenic PCP Pincer-Aryl Ruthenium(II) Complexes and Their Use in the Asymmetric Hydrogen Transfer Reaction of Acetophenone. Helv Chim Acta 2005. [DOI: 10.1002/hlca.200590048] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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443
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Cong FD, Wang YH, Ma CY, Yu HF, Han SP, Tao J, Cao SG. A way for resolution of (R, S)-2-octanol by combining dynamic kinetic resolution with double kinetic resolution. Enzyme Microb Technol 2005. [DOI: 10.1016/j.enzmictec.2004.12.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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444
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Wuyts S, De Temmerman K, De Vos DE, Jacobs PA. Acid Zeolites as Alcohol Racemization Catalysts: Screening and Application in Biphasic Dynamic Kinetic Resolution. Chemistry 2005; 11:386-97. [PMID: 15565578 DOI: 10.1002/chem.200400713] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Acid zeolites were screened as heterogeneous catalysts for racemization of benzylic alcohols. The most promising zeolites appeared to be H-Beta zeolites, for which the optimal reaction conditions were studied in further detail. The zeolite performance was compared to that of homogeneous acids and acid resins under similar reaction conditions. In a second part of the research, H-Beta zeolites were applied in dynamic kinetic resolution (DKR) of 1-phenylethanol, which was conducted by means of a two-phase approach and which resulted in yields smoothly crossing the 50% border up to 90%, with an enantiomeric excess of >99%. To explore the applicability of this biphasic methodology, several other substrates were examined in the standard racemization reaction and in the biphasic dynamic kinetic resolution.
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Affiliation(s)
- S Wuyts
- Centre for Surface Chemistry and Catalysis, KULeuven, Kasteelpark Arenberg 23, 3001 Leuven, Belgium
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445
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Legros J, Dehli J, Bolm C. Applications of Catalytic Asymmetric Sulfide Oxidations to the Syntheses of Biologically Active Sulfoxides. Adv Synth Catal 2005. [DOI: 10.1002/adsc.200404206] [Citation(s) in RCA: 364] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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446
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Parvulescu A, De Vos D, Jacobs P. Efficient dynamic kinetic resolution of secondary amines with Pd on alkaline earth salts and a lipase. Chem Commun (Camb) 2005:5307-9. [PMID: 16244737 DOI: 10.1039/b509747a] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Combination of Pd, supported on alkaline earth type supports with a lipase results in a selective catalytic system for dynamic kinetic resolution of benzylic amines.
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Affiliation(s)
- Andrei Parvulescu
- Centre for Surface Chemistry and Catalysis, Katholieke Universiteit Leuven, Kasteelpark Arenberg 23, 3001 Leuven, Belgium
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447
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Kita Y, Akai S. 1-alkoxyvinyl esters: renaissance of half-century-old acyl donors with potential applicability. CHEM REC 2005; 4:363-72. [PMID: 15739198 DOI: 10.1002/tcr.20027] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Among the various kinds of acyl donors, the 1-alkoxyvinyl esters have characteristic features, such as a high reactivity under nearly neutral conditions and the generation of neutral and volatile esters as single coproducts. Although their use in organic syntheses began in the middle of the 1950s, no significant progress has been seen. This is probably because the existing method of preparing alkoxyvinyl esters used toxic mercuric salts and was not totally applicable for those esters having functionalized acyl moieties. We have discovered that the use of a catalytic amount of the less toxic [RuCl2(p-cymene)]2 effectively accelerates the addition of carboxylic acids to ethoxyacetylene to give ethoxyvinyl esters bearing a variety of functionalized acyl groups in high yields. This discovery has opened a new avenue for developing new reactions and new synthetic methodologies based on the design and use of these acyl donors with suitable functional groups. Such examples include (i) the installation of hydrophilic acyl moieties on biologically active compounds, (ii) asymmetric Pummerer-type reactions, (iii) aromatic Pummerer-type reactions, (iv) the lipase-catalyzed desymmetrization of symmetrical 1,3-diols, and (v) lipase-catalyzed domino reactions. Future possibilities for these acyl donors are also discussed.
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Affiliation(s)
- Yasuyuki Kita
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan.
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448
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Black PJ, Edwards MG, Williams JM. Catalytic electronic activation as a tool for the addition of stabilised nucleophiles to allylic alcohols. Tetrahedron 2005. [DOI: 10.1016/j.tet.2004.10.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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449
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Glueck SM, Larissegger-Schnell B, Csar K, Kroutil W, Faber K. Biocatalytic racemisation of α-hydroxycarboxylic acids at physiological conditions. Chem Commun (Camb) 2005:1904-5. [PMID: 15795782 DOI: 10.1039/b418786e] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Biocatalytic racemisation of aliphatic, aryl-aliphatic and aromatic alpha-hydroxycarboxylic acids was accomplished using whole resting cells of Lactobacillus paracasei DSM 20207; the mild (physiological) reaction conditions ensured an essentially 'clean' isomerization in the absence of side reactions, such as elimination or decomposition.
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Affiliation(s)
- Silvia M Glueck
- Department of Chemistry, Organic and Bioorganic Chemistry, Research Centre Applied Biocatalysis, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria.
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450
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Wallner SR, Nestl BM, Faber K. Highly enantioselective stereo-inverting sec-alkylsulfatase activity of hyperthermophilic Archaea. Org Biomol Chem 2005; 3:2652-6. [PMID: 15999201 DOI: 10.1039/b504883d] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
rac-sec-Alkyl sulfate esters 1a-8a were resolved in low to excellent enantioselectivities with E-values up to >200 using whole cells of aerobically-grown hyperthermophilic sulfur-metabolizers, such as Sulfolobus solfataricus DSM 1617, Sulfolobus shibatae DSM 5389 and, most notably, Sulfolobus acidocaldarius DSM 639. Significantly enhanced selectivities were obtained using cells grown on sucrose-enriched Brock-medium. The stereochemical course of this biohydrolysis was shown to proceed with strict inversion of configuration, thus the preferred (R)-enantiomers were converted into the corresponding (S)-sec-alcohols to furnish a homochiral product mixture.
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Affiliation(s)
- Sabine R Wallner
- Department of Chemistry, Organic and Bioorganic Chemistry, University of Graz, Heinrichstrasse 28, A-8010 Graz, Austria
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