601
|
Chandra A, Singh B, Upadhyay S, Singh RM. Copper-free Sonogashira coupling of 2-chloroquinolines with phenyl acetylene and quick annulation to benzo[b][1,6]naphthyridine derivatives in aqueous ammonia. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.10.010] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
602
|
Enantioselective synthesis of polysubstituted prolines by Binap-silver-catalyzed 1,3-dipolar cycloadditions. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.tetasy.2008.12.021] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
603
|
He R, Wang X, Hashimoto T, Maruoka K. Binaphthyl-Modified Quaternary Phosphonium Salts as Chiral Phase-Transfer Catalysts: Asymmetric Amination of β-Keto Esters. Angew Chem Int Ed Engl 2008; 47:9466-8. [DOI: 10.1002/anie.200804140] [Citation(s) in RCA: 181] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
604
|
He R, Wang X, Hashimoto T, Maruoka K. Binaphthyl-Modified Quaternary Phosphonium Salts as Chiral Phase-Transfer Catalysts: Asymmetric Amination of β-Keto Esters. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200804140] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
605
|
Enantioselective α-Hydrazination of α-Fluoro-β-Ketoesters Catalyzed by Bifunctional Organocatalysts. B KOREAN CHEM SOC 2008. [DOI: 10.5012/bkcs.2008.29.11.2091] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
606
|
Liu WJ, Chen XH, Gong LZ. Direct Assembly of Aldehydes, Amino Esters, and Anilines into Chiral Imidazolidines via Brønsted Acid Catalyzed Asymmetric 1,3-Dipolar Cycloadditions. Org Lett 2008; 10:5357-60. [DOI: 10.1021/ol802177s] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Wei-Jun Liu
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Xiao-Hua Chen
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Liu-Zhu Gong
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| |
Collapse
|
607
|
Syntheses, X-ray, MSn, NMR and CD structure determination of nickel(II) complexes of Schiff bases of (S)-N-(2-benzoylphenyl)-1-benzylpyrrolidine-2-carboxamide and aromatic α-amino acids. Polyhedron 2008. [DOI: 10.1016/j.poly.2008.08.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
608
|
Hirner S, Kirchner DK, Somfai P. Synthesis of α-Amino Acids by Umpolung of Weinreb Amide Enolates. European J Org Chem 2008. [DOI: 10.1002/ejoc.200800683] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
609
|
Tan C, Liu X, Wang L, Wang J, Feng X. Highly enantioselective aza-Henry reaction of ketoimines catalyzed by chiral N,N'-dioxide-copper(I) complexes. Org Lett 2008; 10:5305-8. [PMID: 18954056 DOI: 10.1021/ol802236h] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The first example of catalytic enantioselective aza-Henry reaction of ketoimines has been realized using a simple chiral N,N'-dioxide-Cu(I) complex as catalyst. It performs well over a range of substrates to give the corresponding products in moderate to good yields (up to 83%) with high enantioselectivities (up to 96% ee).
Collapse
Affiliation(s)
- Cheng Tan
- Key Laboratory of Green Chemistry & Technology, Ministry of Education, College of Chemistry, Sichuan University, Chengdu, PR China
| | | | | | | | | |
Collapse
|
610
|
Enantioselective Electrophilic α-Amination of α-Cyanoketones Catalyzed by Chiral Nickel Complexes. B KOREAN CHEM SOC 2008. [DOI: 10.5012/bkcs.2008.29.10.2036] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
611
|
Solution and fluorous phase synthesis of β,β-difluorinated 1-amino-1-cyclopentane carboxylic acid derivatives. J Fluor Chem 2008. [DOI: 10.1016/j.jfluchem.2008.04.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
612
|
Mohr JT, Krout MR, Stoltz BM. Natural products as inspiration for the development of asymmetric catalysis. Nature 2008; 455:323-32. [PMID: 18800131 PMCID: PMC2562237 DOI: 10.1038/nature07370] [Citation(s) in RCA: 190] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Biologically active natural products often contain particularly challenging structural features and functionalities in terms of synthesis. Perhaps the greatest difficulties are those caused by issues of stereochemistry. A useful strategy for synthesizing such molecules is to devise methods of bond formation that provide opportunities for using enantioselective catalysis. In using this tactic, the desire for a particular target structure ultimately drives the development of catalytic methods. New enantioselective catalytic methods contribute to a greater fundamental understanding of how bonds can be constructed and lead to valuable synthetic technologies that are useful for a variety of applications.
Collapse
Affiliation(s)
| | | | - Brian M. Stoltz
- The Arnold and Mabel Beckman Laboratories of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Boulevard, MC 164-30, Pasadena, CA 91125 (USA)
| |
Collapse
|
613
|
Leung D, Folmer-Andersen JF, Lynch VM, Anslyn EV. Using enantioselective indicator displacement assays to determine the enantiomeric excess of alpha-amino acids. J Am Chem Soc 2008; 130:12318-27. [PMID: 18714996 PMCID: PMC7811882 DOI: 10.1021/ja803806c] [Citation(s) in RCA: 121] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Enantioselective indicator displacement assays (eIDAs) were used for the determination of enantiomeric excess (ee) of alpha-amino acids as an alternative to the labor-intensive technique of chromatography. In this study, eIDAs were implemented by the use of two chiral receptors [(Cu(II)(1)](2+), [Cu(II)(2)](2+)) in conjunction with the indicator chrome azurol S. The two receptors were able to enantioselectively discriminate 13 of the 17 analyzed alpha-amino acids. Enantiomeric excess calibration curves were made using both receptors and then used to analyze true test samples to check the system's ability to determine ee accurately. The proposed method uses a conventional UV-vis spectrophotometer to monitor the colorimetric signal, which allows for a potential high-throughput screening (HTS) method for determining ee. The techniques created consistently produced results accurate enough for rapid preliminary determination of ee.
Collapse
Affiliation(s)
- Diana Leung
- Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, Texas 78712, USA
| | | | | | | |
Collapse
|
614
|
Lu TJ, Lin CK. Asymmetric Synthesis of α-Amino Acids: Preparation and Alkylation of Monocyclic Iminolactones Derived from α-Methyl trans-Cinnamaldehyde. J Org Chem 2008; 73:9527-34. [DOI: 10.1021/jo801514g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Ta-Jung Lu
- Department of Chemistry, National Chung-Hsing University, Taichung, Taiwan 40227, Republic of China
| | - Cheng-Kun Lin
- Department of Chemistry, National Chung-Hsing University, Taichung, Taiwan 40227, Republic of China
| |
Collapse
|
615
|
A practical approach to non-natural or N-unsubstituted α-arylglycine derivatives: Hf(OTf)4-doped Me3SiCl system-catalyzed aminomethylation of electron-rich arenes with a new type of N,O-acetal. Tetrahedron 2008. [DOI: 10.1016/j.tet.2008.07.052] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
616
|
Jung SH, Kim DY. Catalytic enantioselective electrophilic α-hydrazination of β-ketoesters using bifunctional organocatalysts. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.07.041] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
617
|
Cabrera S, Reyes E, Alemán J, Milelli A, Kobbelgaard S, Jørgensen KA. Organocatalytic Asymmetric Synthesis of α,α-Disubstituted α-Amino Acids and Derivatives. J Am Chem Soc 2008; 130:12031-7. [DOI: 10.1021/ja804567h] [Citation(s) in RCA: 159] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Silvia Cabrera
- Danish National Research Foundation: Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Efraim Reyes
- Danish National Research Foundation: Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - José Alemán
- Danish National Research Foundation: Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Andrea Milelli
- Danish National Research Foundation: Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Sara Kobbelgaard
- Danish National Research Foundation: Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Karl Anker Jørgensen
- Danish National Research Foundation: Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| |
Collapse
|
618
|
Abstract
Enamides display a fine balance of stability and reactivity, which is now leading to their increasing use in organic synthesis. Enamides offer multiple opportunities for the inclusion of nitrogen based functionality into organic systems. Recent examples of these compounds as substrates are discussed in this article.
Collapse
|
619
|
Nájera C, Retamosa M, Sansano J. Catalytic Enantioselective 1,3-Dipolar Cycloaddition Reactions of Azomethine Ylides and Alkenes by Using Phosphoramidite-Silver(I) Complexes. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200801690] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
620
|
Nájera C, Retamosa M, Sansano J. Catalytic Enantioselective 1,3-Dipolar Cycloaddition Reactions of Azomethine Ylides and Alkenes by Using Phosphoramidite-Silver(I) Complexes. Angew Chem Int Ed Engl 2008; 47:6055-8. [DOI: 10.1002/anie.200801690] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
621
|
Kobayashi S, Yazaki R, Seki K, Yamashita Y. The Fluorenone Imines of Glycine Esters and Their Phosphonic Acid Analogues. Angew Chem Int Ed Engl 2008; 47:5613-5. [DOI: 10.1002/anie.200801322] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
622
|
|
623
|
Ruiz N, Vicario JL, Badía D, Carrillo L, Alonso B. (S,S)-(+)-Pseudoephedrine α-Iminoglyoxylamide as a Chiral Glycine Cation Equivalent: A Modular and Flexible Approach to Enantioenriched α-Amino Ketones. Org Lett 2008; 10:2613-6. [DOI: 10.1021/ol800934r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nerea Ruiz
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, P.O. Box 644, 48080 Bilbao, Spain
| | - Jose L. Vicario
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, P.O. Box 644, 48080 Bilbao, Spain
| | - Dolores Badía
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, P.O. Box 644, 48080 Bilbao, Spain
| | - Luisa Carrillo
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, P.O. Box 644, 48080 Bilbao, Spain
| | - Beatriz Alonso
- Departamento de Química Orgánica II, Facultad de Ciencia y Tecnología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, P.O. Box 644, 48080 Bilbao, Spain
| |
Collapse
|
624
|
Abstract
Chiral biphenols catalyze the enantioselective Petasis reaction of alkenyl boronates, secondary amines, and ethyl glyoxylate. The reaction requires the use of 15 mol % of (S)-VAPOL as the catalyst, alkenyl boronates as nucleophiles, ethyl glyoxylate as the aldehyde component, and 3 A molecular sieves as an additive. The chiral alpha-amino ester products are obtained in good yields (71-92%) and high enantiomeric ratios (89:11-98:2). Mechanistic investigations indicate single ligand exchange of acyclic boronate with VAPOL and tetracoordinate boronate intermediates.
Collapse
Affiliation(s)
- Sha Lou
- Department of Chemistry, Center for Chemical Methodology and Library Development, Boston University, 24 Cummington Street, Boston, Massachusetts 02215, USA
| | | |
Collapse
|
625
|
Experimental and theoretical studies on the asymmetric cyanosilylation of C2-symmetric hydrazones. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.tetasy.2008.03.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
626
|
von Nussbaum F, Anlauf S, Freiberg C, Benet-Buchholz J, Schamberger J, Henkel T, Schiffer G, Häbich D. Total Synthesis and Initial Structure–Activity Relationships of Longicatenamycin A. ChemMedChem 2008; 3:619-26. [DOI: 10.1002/cmdc.200700297] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
627
|
Navarre L, Martinez R, Genet JP, Darses S. Access to Enantioenriched α-Amino Esters via Rhodium-Catalyzed 1,4-Addition/Enantioselective Protonation. J Am Chem Soc 2008; 130:6159-69. [DOI: 10.1021/ja710691p] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Laure Navarre
- Laboratoire de Synthèse Sélective Organique (UMR 7573, CNRS), Ecole Nationale Supérieure de Chimie de Paris, 11 rue P&M Curie, 75231 Paris cedex 05, France
| | - Rémi Martinez
- Laboratoire de Synthèse Sélective Organique (UMR 7573, CNRS), Ecole Nationale Supérieure de Chimie de Paris, 11 rue P&M Curie, 75231 Paris cedex 05, France
| | - Jean-Pierre Genet
- Laboratoire de Synthèse Sélective Organique (UMR 7573, CNRS), Ecole Nationale Supérieure de Chimie de Paris, 11 rue P&M Curie, 75231 Paris cedex 05, France
| | - Sylvain Darses
- Laboratoire de Synthèse Sélective Organique (UMR 7573, CNRS), Ecole Nationale Supérieure de Chimie de Paris, 11 rue P&M Curie, 75231 Paris cedex 05, France
| |
Collapse
|
628
|
Reetz M. Kombinatorische Übergangsmetallkatalyse: Mischungen einzähniger Liganden zur Kontrolle der Enantio-, Diastereo- und Regioselektivität. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200704327] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
629
|
Reetz M. Combinatorial Transition-Metal Catalysis: Mixing Monodentate Ligands to Control Enantio-, Diastereo-, and Regioselectivity. Angew Chem Int Ed Engl 2008; 47:2556-88. [DOI: 10.1002/anie.200704327] [Citation(s) in RCA: 223] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
630
|
Elsner P, Bernardi L, Salla GD, Overgaard J, Jørgensen KA. Organocatalytic Asymmetric Conjugate Addition to Allenic Esters and Ketones. J Am Chem Soc 2008; 130:4897-905. [DOI: 10.1021/ja710689c] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Petteri Elsner
- Danish National Research Foundation, Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Luca Bernardi
- Danish National Research Foundation, Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Giorgio Dela Salla
- Danish National Research Foundation, Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Jacob Overgaard
- Danish National Research Foundation, Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Karl Anker Jørgensen
- Danish National Research Foundation, Center for Catalysis, Department of Chemistry, Aarhus University, DK-8000 Aarhus C, Denmark
| |
Collapse
|
631
|
Thomson JE, Campbell CD, Concellón C, Duguet N, Rix K, Slawin AMZ, Smith AD. Probing the Efficiency of N-Heterocyclic Carbene Promoted O- to C-Carboxyl Transfer of Oxazolyl Carbonates. J Org Chem 2008; 73:2784-91. [DOI: 10.1021/jo702720a] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jennifer E. Thomson
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K
| | - Craig D. Campbell
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K
| | - Carmen Concellón
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K
| | - Nicolas Duguet
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K
| | - Kathryn Rix
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K
| | - Alexandra M. Z. Slawin
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K
| | - Andrew D. Smith
- EaStCHEM, School of Chemistry, University of St. Andrews, North Haugh, St. Andrews KY16 9ST, U.K
| |
Collapse
|
632
|
Hirner S, Panknin O, Edefuhr M, Somfai P. Synthesis of Aryl Glycines by the α Arylation of Weinreb Amides. Angew Chem Int Ed Engl 2008. [DOI: 10.1002/ange.200704689] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
633
|
Hirner S, Panknin O, Edefuhr M, Somfai P. Synthesis of Aryl Glycines by the α Arylation of Weinreb Amides. Angew Chem Int Ed Engl 2008; 47:1907-9. [DOI: 10.1002/anie.200704689] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
634
|
Highly efficient polymer supported phase-transfer catalysts containing hydrogen bond inducing functional groups. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2007.12.077] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
635
|
Chinchilla R, Nájera C, Ortega FJ. Enantioselective cyanoformylation of aldehydes using a recyclable dimeric cinchonidine ammonium salt as an organocatalyst. ACTA ACUST UNITED AC 2008. [DOI: 10.1016/j.tetasy.2008.01.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
636
|
Kobayashi S, Tsubogo T, Saito S, Yamashita Y. Calcium-Catalyzed Diastereo- and Enantioselective 1,4-Addition of Glycine Derivatives to α,β-Unsaturated Esters. Org Lett 2008; 10:807-9. [DOI: 10.1021/ol702958w] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shū Kobayashi
- Department of Chemistry, School of Science and Graduate School of Pharmaceutical Sciences, The University of Tokyo, The HFRE Division, ERATO, Japan Science Technology Agency (JST), Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Tetsu Tsubogo
- Department of Chemistry, School of Science and Graduate School of Pharmaceutical Sciences, The University of Tokyo, The HFRE Division, ERATO, Japan Science Technology Agency (JST), Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Susumu Saito
- Department of Chemistry, School of Science and Graduate School of Pharmaceutical Sciences, The University of Tokyo, The HFRE Division, ERATO, Japan Science Technology Agency (JST), Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Yasuhiro Yamashita
- Department of Chemistry, School of Science and Graduate School of Pharmaceutical Sciences, The University of Tokyo, The HFRE Division, ERATO, Japan Science Technology Agency (JST), Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| |
Collapse
|
637
|
Griesbeck AG, Bondock S. Photocycloaddition of 5-Methoxyoxazoles to Aldehydes and ?-Keto Esters: A Comprehensive View on Stereoselectivity, Triplet Biradical Conformations, and Synthetic Applications of Paternò–Büchi Adducts. Aust J Chem 2008. [DOI: 10.1071/ch08168] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The photocycloaddition of carbonyl compounds (aldehydes and keto esters, respectively) with 5-methoxyoxazoles bearing substituents at C2 and C4 is described with respect to regio- and diastereoselectivity. In all cases the reactions proceed with excellent regioselectivity and with high to moderate (exo) diastereoselectivity independent of the nature of the excited carbonyl compound. The products can be easily ring-opened to give α-amino, β-hydroxy carboxylic acid derivatives.
Collapse
|
638
|
de Boer JW, Browne WR, Harutyunyan SR, Bini L, Tiemersma-Wegman TD, Alsters PL, Hage R, Feringa BL. Manganese catalysed asymmetric cis-dihydroxylation with H2O2. Chem Commun (Camb) 2008:3747-9. [DOI: 10.1039/b808355j] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
639
|
Ntaganda R, Milovic T, Tiburcio J, Thadani AN. Direct, facile synthesis of N-acyl-α-amino amides from α-keto esters and ammonia. Chem Commun (Camb) 2008:4052-4. [DOI: 10.1039/b808302a] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
640
|
Chinchilla R, Nájera C, Ortega FJ. Convenient Conditions for the Enantioselective Synthesis of α-Methyl-α-amino Acids with the Use ofCinchonaAmmonium Salts as Phase-Transfer Organocatalysts. European J Org Chem 2007. [DOI: 10.1002/ejoc.200700925] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|