1
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Durin G, Berthet JC, Nicolas E, Cantat T. Unlocking the Catalytic Hydrogenolysis of Chlorosilanes into Hydrosilanes with Superbases. ACS Catal 2021. [DOI: 10.1021/acscatal.1c01515] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Gabriel Durin
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette Cedex, France
| | - Jean-Claude Berthet
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette Cedex, France
| | - Emmanuel Nicolas
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette Cedex, France
| | - Thibault Cantat
- Université Paris-Saclay, CEA, CNRS, NIMBE, 91191 Gif-sur-Yvette Cedex, France
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2
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Burke JR, La Clair JJ, Philippe RN, Pabis A, Corbella M, Jez JM, Cortina GA, Kaltenbach M, Bowman ME, Louie GV, Woods KB, Nelson AT, Tawfik DS, Kamerlin SC, Noel JP. Bifunctional Substrate Activation via an Arginine Residue Drives Catalysis in Chalcone Isomerases. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01926] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Jason R. Burke
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - James J. La Clair
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - Ryan N. Philippe
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - Anna Pabis
- Department of Cell and Molecular Biology, Uppsala University, BMC Box 596, S-751 24 Uppsala, Sweden
| | - Marina Corbella
- Department of Chemistry−BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Joseph M. Jez
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - George A. Cortina
- Department of Molecular Physiology and Biomedical Engineering, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Miriam Kaltenbach
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Marianne E. Bowman
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - Gordon V. Louie
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - Katherine B. Woods
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - Andrew T. Nelson
- Department of Chemistry, University of Texas at Austin, Austin, Texas 78712, United States
| | - Dan S. Tawfik
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot 76100, Israel
| | - Shina C.L. Kamerlin
- Department of Chemistry−BMC, Uppsala University, BMC Box 576, S-751 23 Uppsala, Sweden
| | - Joseph P. Noel
- Howard Hughes Medical Institute, Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, California 92037, United States
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3
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Cui XY, Tan CH, Leow D. Metal-catalysed reactions enabled by guanidine-type ligands. Org Biomol Chem 2019; 17:4689-4699. [DOI: 10.1039/c8ob02240b] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A review of metal–guanidine complexes, which are selective and powerful catalysts for organic transformations, asymmetric synthesis, and polymerisation.
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Affiliation(s)
- Xi-Yang Cui
- Division of Chemistry and Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore 637371
| | - Choon-Hong Tan
- Division of Chemistry and Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore 637371
| | - Dasheng Leow
- Division of Chemistry and Biological Chemistry
- School of Physical and Mathematical Sciences
- Nanyang Technological University
- Singapore 637371
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4
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Turočkin A, Raven W, Selig P. Synthesis of Bicyclic and Tricyclic Chiral Guanidinium Salts by an Intramolecular Alkylation Approach. European J Org Chem 2016. [DOI: 10.1002/ejoc.201601154] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- Aleksej Turočkin
- Institute of Organic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - William Raven
- Institute of Inorganic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Philipp Selig
- Institute of Organic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
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5
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Xue H, Tan CH, Wong MW. Guanidine-catalyzed asymmetric Strecker reaction: modes of activation and origin of stereoselectivity. CAN J CHEM 2016. [DOI: 10.1139/cjc-2016-0307] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Density functional theory calculations were employed to study the catalytic mechanism, modes of activation, and origin of enantioselectivity of guanidine-catalyzed asymmetric Strecker reaction of N-benzhydryl imine with hydrogen cyanide. Two types of bifunctional activation mode were identified, namely conventional bifunctional Brønsted acid activation and unconventional bifunctional Brønsted–Lewis acid activation. The lowest-energy transition states correspond to the conventional bifunctional mode of activation. The calculated enantiomeric excess, based on eight lowest-energy C–C bond forming transition states, is in good accord with observed enantioselectivity. NCI (noncovalent interaction) analysis of the key transition states reveals extensive noncovalent interactions, including aromatic interactions and hydrogen bonds, between the guanidinium catalyst and substrates. Multiple aryl–aryl interactions between the phenyl groups of guanidine catalyst and the phenyl rings of N-benzhydryl imine are the key stabilizations in the most stable (R)-inducing transition state. Differential attractive aryl–aryl stabilization is the major factor for stereoinduction.
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Affiliation(s)
- Hansong Xue
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Choon-Hong Tan
- Department of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
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6
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Cho B, Wong MW. Unconventional Bifunctional Lewis-Brønsted Acid Activation Mode in Bicyclic Guanidine-Catalyzed Conjugate Addition Reactions. Molecules 2015; 20:15108-21. [PMID: 26295222 PMCID: PMC6331857 DOI: 10.3390/molecules200815108] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Revised: 06/03/2015] [Accepted: 08/10/2015] [Indexed: 01/26/2023] Open
Abstract
DFT calculations have demonstrated that the unconventional bifunctional Brønsted-Lewis acid activation mode is generally applicable to a range of nucleophilic conjugate additions catalyzed by bicyclic guanidine catalysts. It competes readily with the conventional bifunctional Brønsted acid mode of activation. The optimal pro-nucleophiles for this unconventional bifunctional activation are acidic substrates with low pKa, while the best electrophiles are flexible 1,4-diamide and 1,4-diester conjugated systems.
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Affiliation(s)
- Bokun Cho
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
| | - Ming Wah Wong
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Singapore.
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7
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Xue H, Jiang D, Jiang H, Kee CW, Hirao H, Nishimura T, Wong MW, Tan CH. Mechanistic Insights into Bicyclic Guanidine-Catalyzed Reactions from Microscopic and Macroscopic Perspectives. J Org Chem 2015; 80:5745-52. [DOI: 10.1021/acs.joc.5b00709] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Hansong Xue
- Department
of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Danfeng Jiang
- Department
of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Huan Jiang
- Department
of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Choon Wee Kee
- Department
of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Hajime Hirao
- Department
of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
| | - Takahiro Nishimura
- Department
of Chemistry, Kyoto University, Sakyo-ku, Kyoto 6068502, Japan
| | - Ming Wah Wong
- Department
of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
| | - Choon-Hong Tan
- Department
of Chemistry and Biological Chemistry, Nanyang Technological University, 21 Nanyang Link, Singapore 637371
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8
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Wei J, Wang P, Jia Q, Huang J, Du Z, Zhang K, Wang J. Amine-Catalyzed Cascade Synthesis of 3,4-Diunsubstituted Coumarins. European J Org Chem 2013. [DOI: 10.1002/ejoc.201300538] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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9
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Zhang W, Tan D, Lee R, Tong G, Chen W, Qi B, Huang KW, Tan CH, Jiang Z. Highly Enantio- and Diastereoselective Reactions of γ-Substituted Butenolides Through Direct Vinylogous Conjugate Additions. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201205872] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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10
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Zhang W, Tan D, Lee R, Tong G, Chen W, Qi B, Huang KW, Tan CH, Jiang Z. Highly Enantio- and Diastereoselective Reactions of γ-Substituted Butenolides Through Direct Vinylogous Conjugate Additions. Angew Chem Int Ed Engl 2012; 51:10069-73. [DOI: 10.1002/anie.201205872] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2012] [Indexed: 11/11/2022]
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11
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Peng S, Wang L, Guo H, Sun S, Wang J. Facile synthesis of 4-substituted 3,4-dihydrocoumarins via an organocatalytic double decarboxylation process. Org Biomol Chem 2012; 10:2537-41. [PMID: 22366754 DOI: 10.1039/c2ob25075f] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
3,4-Dihydrocoumarins, considered to be valuable building blocks, have attracted considerable attention due to their various biological activities. Herein, we have documented an efficient and convenient double decarboxylation process for the synthesis of 4-substituted 3,4-dihydrocoumarin in moderate to excellent yields under mild reaction conditions (up to 98%).
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Affiliation(s)
- Shiyong Peng
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
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12
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Wang J, Chen J, Kee CW, Tan CH. Enantiodivergent and γ-Selective Asymmetric Allylic Amination. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201107317] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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13
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Wang J, Chen J, Kee CW, Tan CH. Enantiodivergent and γ-Selective Asymmetric Allylic Amination. Angew Chem Int Ed Engl 2012; 51:2382-6. [DOI: 10.1002/anie.201107317] [Citation(s) in RCA: 77] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2011] [Revised: 12/21/2011] [Indexed: 11/06/2022]
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14
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Li L, Chen W, Yang W, Pan Y, Liu H, Tan CH, Jiang Z. Bicyclic guanidine-catalyzed asymmetric Michael additions of 3-benzyl-substituted oxindoles to N-maleimides. Chem Commun (Camb) 2012; 48:5124-6. [DOI: 10.1039/c2cc31587d] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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15
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Zhao Y, Lim X, Pan Y, Zong L, Feng W, Tan CH, Huang KW. Asymmetric H–D exchange reactions of fluorinated aromatic ketones. Chem Commun (Camb) 2012; 48:5479-81. [DOI: 10.1039/c2cc31443f] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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16
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Zhao F, Wang Y, Zhang WX, Xi Z. Metal-free synthesis of cyclic di-oxoguanidines via one-pot sequential transformation of amines, carbodiimides and acyl dichlorides. Org Biomol Chem 2012; 10:6266-70. [DOI: 10.1039/c2ob25799h] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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17
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Li D, Wang Y, Zhang WX, Zhang S, Guang J, Xi Z. One-Pot Synthesis and Unpredicted Hydrogen Bonds of the Guanidinium Triflates from Readily Available Amines, Carbodiimides, and Zn(OTf)2. Organometallics 2011. [DOI: 10.1021/om2006613] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dongzhen Li
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Yang Wang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Wen-Xiong Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
- State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin, 300071, China
| | - Shaoguang Zhang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Jie Guang
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
| | - Zhenfeng Xi
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China
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Pan Y, Kee CW, Jiang Z, Ma T, Zhao Y, Yang Y, Xue H, Tan CH. Expanding the utility of Brønsted base catalysis: biomimetic enantioselective decarboxylative reactions. Chemistry 2011; 17:8363-70. [PMID: 21678511 DOI: 10.1002/chem.201100687] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2011] [Indexed: 11/11/2022]
Abstract
As a result of the low reactivity of simple esters, the use of them as nucleophiles in direct asymmetric transformations is a long-standing challenge in synthetic organic chemistry. Nature approaches this difficulty through a decarboxylative mechanism, which is used for polyketide synthesis. Inspired by nature, we report guanidine-catalyzed biomimetic decarboxylative C-C and C-N bond-formation reactions. These highly enantioselective decarboxylative Mannich and amination reactions utilized malonic acid half thioesters as simple ester surrogates. It is proposed that nucleophilic addition precedes decarboxylation in the mechanism, which has been investigated in detail through the identification of intermediates by using electrospray ionization (ESI) mass-spectrometric analysis and DFT calculations.
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Affiliation(s)
- Yuanhang Pan
- Department of Chemistry, National University of Singapore (NUS), 3 Science Drive 3, 117543, Singapore
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19
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Cho B, Tan CH, Wong MW. Sequential catalytic role of bifunctional bicyclic guanidine in asymmetric phospha-Michael reaction. Org Biomol Chem 2011; 9:4550-7. [PMID: 21509383 DOI: 10.1039/c1ob05186e] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The catalytic mechanism and origin of enantioselectivity of bicyclic guanidine-catalyzed phospha-Michael reaction between diphenyl phosphine oxide and β-nitrostyrene were investigated by DFT calculations at M06-2X/cc-pVTZ//M06-2X/cc-pVDZ level in conjunction with the implicit SMD solvation method. The catalyst is found to be involved in all 3 steps of the proposed catalytic cycle, namely (1) tautomerization of phosphine oxide, (2) C-P bond formation and (3) concerted hydrogen transfer. The bifunctional role of the guanidine catalyst is clearly demonstrated in all 3 key steps. Due to the geometry of the bicyclic guanidine catalyst, the preferred orientation of the reactants in the transition state of enantioselective C-P bond forming step favours the R enantiomer, in excellent accord with the observed enantioselectivity. Analysis of various transition states suggests that the asymmetric C-P bond formation is controlled by the hydrogen bonding interaction and steric effect between the catalyst and substrate. Various weaker C-H···X (X = N, O and π) interactions also play a role in stabilizing the key transition states.
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Affiliation(s)
- Bokun Cho
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore, 117543
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20
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Fu X, Tan CH. Mechanistic considerations of guanidine-catalyzed reactions. Chem Commun (Camb) 2011; 47:8210-22. [DOI: 10.1039/c0cc03691a] [Citation(s) in RCA: 163] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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21
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Zhang C, Zhu Y, Wei D, Sun D, Zhang W, Tang M. Theoretical Study on the Reaction Mechanism between 6-Benzyl-6-azabicyclo[2.2.1]hept-2-ene and Benzoyl Isocyanate to Urea and Isourea. J Phys Chem A 2010; 114:2913-9. [DOI: 10.1021/jp910173d] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Cong Zhang
- Center of Computational Chemistry, Department of Chemistry, Zhengzhou University, Zhengzhou, Henan Province, 450052, P. R. China
| | - Yanyan Zhu
- Center of Computational Chemistry, Department of Chemistry, Zhengzhou University, Zhengzhou, Henan Province, 450052, P. R. China
| | - Donghui Wei
- Center of Computational Chemistry, Department of Chemistry, Zhengzhou University, Zhengzhou, Henan Province, 450052, P. R. China
| | - Dongzhen Sun
- Center of Computational Chemistry, Department of Chemistry, Zhengzhou University, Zhengzhou, Henan Province, 450052, P. R. China
| | - Wenjing Zhang
- Center of Computational Chemistry, Department of Chemistry, Zhengzhou University, Zhengzhou, Henan Province, 450052, P. R. China
| | - Mingsheng Tang
- Center of Computational Chemistry, Department of Chemistry, Zhengzhou University, Zhengzhou, Henan Province, 450052, P. R. China
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Lee R, Yang Y, Tan GK, Tan CH, Huang KW. A Novel heteroleptic paddlewheel diruthenium bicyclic guanidinate complex: Synthesis, structure, and scope. Dalton Trans 2010; 39:723-5. [DOI: 10.1039/b915881b] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Berlinck RGS, Burtoloso ACB, Trindade-Silva AE, Romminger S, Morais RP, Bandeira K, Mizuno CM. The chemistry and biology of organic guanidine derivatives. Nat Prod Rep 2010; 27:1871-907. [DOI: 10.1039/c0np00016g] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Coles MP, Khalaf MS, Claramunt RM, García MA, Alkorta I, Elguero J. Double proton transfer in crystals of 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a] pyrimidine (hppH): 13C and 15N CPMAS NMR study of (hppH)2. J PHYS ORG CHEM 2009. [DOI: 10.1002/poc.1636] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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25
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Lin S, Leow D, Huang KW, Tan CH. Enantioselective Protonation of Itaconimides with Thiols and the Rotational Kinetics of the Axially Chiral CN Bond. Chem Asian J 2009; 4:1741-4. [DOI: 10.1002/asia.200900331] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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26
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Jiang Z, Pan Y, Zhao Y, Ma T, Lee R, Yang Y, Huang KW, Wong M, Tan CH. Synthesis of a Chiral Quaternary Carbon Center Bearing a Fluorine Atom: Enantio- and Diastereoselective Guanidine-Catalyzed Addition of Fluorocarbon Nucleophiles. Angew Chem Int Ed Engl 2009; 48:3627-31. [DOI: 10.1002/anie.200900964] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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27
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Jiang Z, Pan Y, Zhao Y, Ma T, Lee R, Yang Y, Huang KW, Wong M, Tan CH. Synthesis of a Chiral Quaternary Carbon Center Bearing a Fluorine Atom: Enantio- and Diastereoselective Guanidine-Catalyzed Addition of Fluorocarbon Nucleophiles. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200900964] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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28
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Mahé O, Frath D, Dez I, Marsais F, Levacher V, Brière JF. TBD-organocatalysed synthesis of pyrazolines. Org Biomol Chem 2009; 7:3648-51. [DOI: 10.1039/b911577c] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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