1
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Khangarot RK, Khandelwal M, Ray SK. Syntheses and Applications of Singh’s Catalyst. SYNTHESIS-STUTTGART 2020. [DOI: 10.1055/s-0040-1707235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Singh’s catalyst has emerged as one of the most promising and valuable catalysts in the field of asymmetric synthesis. Since its discovery, it has proven to be one of the best organocatalysts for asymmetric direct aldol reactions, and is equally efficient in aqueous and organic media. In this Short Review, we summarize reactions utilizing Singh’s catalyst under various conditions.1 Introduction2 Synthesis of Singh’s Catalyst3 Applications in Asymmetric Synthesis4 Conclusion
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Affiliation(s)
- Rama Kanwar Khangarot
- Department of Chemistry, University College of Science, Mohanlal Sukhadia University
| | - Manisha Khandelwal
- Department of Chemistry, University College of Science, Mohanlal Sukhadia University
| | - Sumit Kumar Ray
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal
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2
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Recent advances in reactions promoted by amino acids and oligopeptides. PHYSICAL SCIENCES REVIEWS 2020. [DOI: 10.1515/psr-2018-0086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
During the last 20 years, Organocatalysis has become one of the major fields of Catalysis. Herein, we provide a recent overview on reactions where the use of amino acids and peptides as the organocatalysts was employed. All aspects regarding aldol reactions, Michael reactions, epoxidation, Henry reactions and many others that are crucial for the reaction conditions and reaction mechanisms are discussed.
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3
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Xu D, Ye F, Ye J, Gao Y, Chen H. Manipulation of Water for Diversified Functionalization of Tetrahydro-β-carbolines (THβCs) with Indoles. Org Lett 2019; 21:6160-6163. [PMID: 31339328 DOI: 10.1021/acs.orglett.9b02413] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Water plays a crucial role in organic synthesis. However, diversified functionalization manipulated by water is still rare and remains unexplored. Herein, we report the first water-manipulated protocol to achieve the diversified functionalization of tetrahydro-β-carbolines (THβCs) in an open flask at room temperature that exhibit a broad functional-group tolerance. More water leads to monoarylation, while less water leads to diarylation. Further one-step transformation afforded oxidized bis(indolyl)methanes, eudistomin U, and the related derivatives in satisfactory yields.
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Affiliation(s)
- Dekang Xu
- Key Laboratory of Molecule Synthesis and Function Discovery (Fuzhou University), Fujian Province University, College of Chemistry , Fuzhou University , Fuzhou , Fujian 350116 , China
| | - Fu Ye
- Key Laboratory of Molecule Synthesis and Function Discovery (Fuzhou University), Fujian Province University, College of Chemistry , Fuzhou University , Fuzhou , Fujian 350116 , China
| | - Jinxiang Ye
- Key Laboratory of Molecule Synthesis and Function Discovery (Fuzhou University), Fujian Province University, College of Chemistry , Fuzhou University , Fuzhou , Fujian 350116 , China
| | - Yu Gao
- Key Laboratory of Molecule Synthesis and Function Discovery (Fuzhou University), Fujian Province University, College of Chemistry , Fuzhou University , Fuzhou , Fujian 350116 , China
| | - Haijun Chen
- Key Laboratory of Molecule Synthesis and Function Discovery (Fuzhou University), Fujian Province University, College of Chemistry , Fuzhou University , Fuzhou , Fujian 350116 , China
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4
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Armacost KA. The Transition from Academia: Overcoming the Barrier to a Career in the Drug Discovery Industry. J Chem Inf Model 2018; 58:1161-1163. [PMID: 29727178 DOI: 10.1021/acs.jcim.8b00262] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This perspective describes the transition from academic training (specifically graduate school and a postdoctoral fellowship) to a career in the pharmaceutical industry as a computational chemist. My personal journey from childhood to senior scientist is described, along with suggestions and insights into a career in the pharmaceutical industry.
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Affiliation(s)
- Kira A Armacost
- Modeling & Informatics, MRL , Merck & Co., Inc. , West Point , Pennsylvania 19486 , United States
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5
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Yan J, Sun R, Shi K, Li K, Yang L, Zhong G. N-Heterocyclic Carbene-Catalyzed Asymmetric Benzoin Reaction in Water. J Org Chem 2018; 83:7547-7552. [DOI: 10.1021/acs.joc.8b00481] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Jun Yan
- College of Materials, Chemistry & Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, China
| | - Rong Sun
- College of Materials, Chemistry & Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, China
| | - Kuangxi Shi
- College of Materials, Chemistry & Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, China
| | - Kai Li
- College of Materials, Chemistry & Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, China
| | - Limin Yang
- College of Materials, Chemistry & Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, China
| | - Guofu Zhong
- College of Materials, Chemistry & Chemical Engineering, Hangzhou Normal University, Hangzhou 310036, China
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6
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Yamashita Y, Yasukawa T, Yoo WJ, Kitanosono T, Kobayashi S. Catalytic enantioselective aldol reactions. Chem Soc Rev 2018; 47:4388-4480. [DOI: 10.1039/c7cs00824d] [Citation(s) in RCA: 165] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Recent developments in catalytic asymmetric aldol reactions have been summarized.
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Affiliation(s)
- Yasuhiro Yamashita
- Department of Chemistry
- School of Science
- The University of Tokyo
- Bunkyo-ku
- Japan
| | - Tomohiro Yasukawa
- Department of Chemistry
- School of Science
- The University of Tokyo
- Bunkyo-ku
- Japan
| | - Woo-Jin Yoo
- Department of Chemistry
- School of Science
- The University of Tokyo
- Bunkyo-ku
- Japan
| | - Taku Kitanosono
- Department of Chemistry
- School of Science
- The University of Tokyo
- Bunkyo-ku
- Japan
| | - Shū Kobayashi
- Department of Chemistry
- School of Science
- The University of Tokyo
- Bunkyo-ku
- Japan
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7
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Xiong Y, Ford NR, Hecht KA, Roesijadi G, Squier TC. Hydrogel Tethering Enhances Interdomain Stabilization of Single-Chain Antibodies. Bioconjug Chem 2017; 28:2804-2814. [DOI: 10.1021/acs.bioconjchem.7b00512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yijia Xiong
- Department
of Basic Medical Sciences, Western University of Health Sciences, Lebanon, Oregon 97355, United States
| | - Nicole R. Ford
- Marine
Biotechnology, Pacific Northwest National Laboratory, Sequim, Washington 98382, United States
| | - Karen A. Hecht
- Marine
Biotechnology, Pacific Northwest National Laboratory, Sequim, Washington 98382, United States
| | - Guritno Roesijadi
- Marine
Biotechnology, Pacific Northwest National Laboratory, Sequim, Washington 98382, United States
- Department
of Microbiology, Oregon State University, Corvallis, Oregon 97331, United States
| | - Thomas C. Squier
- Department
of Basic Medical Sciences, Western University of Health Sciences, Lebanon, Oregon 97355, United States
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8
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Cao S, Yuan H, Yang Y, Wang M, Zhang X, Zhang J. Mechanistic investigation inspired "on water" reaction for hydrobromic acid-catalyzed Friedel-Crafts-type reaction of β-naphthol and formaldehyde. J Comput Chem 2017; 38:2268-2275. [PMID: 28696541 DOI: 10.1002/jcc.24877] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 06/19/2017] [Accepted: 06/20/2017] [Indexed: 01/07/2023]
Abstract
The mechanism of the HBr-catalyzed Friedel-Crafts-type reaction between β-naphthol and HCHO was investigated by DFT to improve this reaction. The HBr-H2 O co-catalyzed the preferential pathway undergoes the concerted nucleophilic addition and hydrogen shift, stepwise followed by H2 O elimination and the CC bond formation. The origin of the high catalytic activity of HBr is ascribed to CH···Br- and OH···Br- interactions, which suggest that the active species is Br- . Moreover, water molecules efficiently assist in improving the activity of Br- . The computational results show that solvent polarity profoundly affects the activation barriers. To our delight, the activation barrier of the rate-determining step for the favored pathway in water is comparable (0.6 kcal/mol difference) with that in acetonitrile. The experimental observation further confirmed our results and demonstrated that the title reaction can be successfully achieved "on water." Therefore, we open a new efficient and green strategy for the synthesis of biphenol derivatives. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Shanshan Cao
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Advanced Energy Materials Research Center, Faculty of Chemistry Northeast Normal University Changchun, 130024, China
| | - Haiyan Yuan
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Advanced Energy Materials Research Center, Faculty of Chemistry Northeast Normal University Changchun, 130024, China
| | - Yang Yang
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Advanced Energy Materials Research Center, Faculty of Chemistry Northeast Normal University Changchun, 130024, China
| | - Mang Wang
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Advanced Energy Materials Research Center, Faculty of Chemistry Northeast Normal University Changchun, 130024, China
| | - Xiaoying Zhang
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Advanced Energy Materials Research Center, Faculty of Chemistry Northeast Normal University Changchun, 130024, China
| | - Jingping Zhang
- Jilin Province Key Laboratory of Organic Functional Molecular Design & Synthesis, Advanced Energy Materials Research Center, Faculty of Chemistry Northeast Normal University Changchun, 130024, China
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9
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Zhao J, He F, Zhang F, Yang X, Tian Z, Xue Y. The Role of Water in the Catalyst-Free Aldol Reaction of Water-Insoluble N-Methyl-2,4-thiazolidinedione with N-Methylisatin from QM/MM Monte Carlo Simulations. Chemphyschem 2017; 18:2123-2131. [PMID: 28544113 DOI: 10.1002/cphc.201700423] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 05/22/2017] [Indexed: 11/08/2022]
Abstract
The role of water in the uncatalyzed aldol reaction of N-methyl-2,4-thiazolidinedione with N-methylisatin is investigated through Monte Carlo statistical mechanics simulations that utilize free energy perturbation theory and the mixed quantum mechanics and molecular mechanics (QM/MM) model with PDDG/PM3 for the QM method in "on-water" and DMSO environments. There are several conceivable orientations between thiazolidinedione and isatin in the process of C-C bond formation. However, the formation of the C-C bond takes place between the re face of isatin and the si face of (E)-enol of the thiazolidinedione to form the preferred anti-type product, which results from enhanced hydrogen-bonding interactions between water molecules and the oxygen atoms undergoing bond breakage and bond formation during the reaction. Novel insights into the effect of water on the aldol reaction are presented herein.
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Affiliation(s)
- Jianming Zhao
- College of Chemistry, Key Lab of Green Chemistry, and Technology in Ministry of Education, Sichuan University, Chengdu, 610064, P.R. China
| | - Fen He
- College of Chemistry, Key Lab of Green Chemistry, and Technology in Ministry of Education, Sichuan University, Chengdu, 610064, P.R. China
| | - Fan Zhang
- College of Chemistry, Key Lab of Green Chemistry, and Technology in Ministry of Education, Sichuan University, Chengdu, 610064, P.R. China
| | - Xin Yang
- College of Chemistry, Key Lab of Green Chemistry, and Technology in Ministry of Education, Sichuan University, Chengdu, 610064, P.R. China
| | - Zhiyue Tian
- College of Chemistry, Key Lab of Green Chemistry, and Technology in Ministry of Education, Sichuan University, Chengdu, 610064, P.R. China
| | - Ying Xue
- College of Chemistry, Key Lab of Green Chemistry, and Technology in Ministry of Education, Sichuan University, Chengdu, 610064, P.R. China
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10
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Allen C, Ghebreab R, Doherty B, Li B, Acevedo O. Examining Ionic Liquid Effects on Mononuclear Rearrangement of Heterocycles Using QM/MM Simulations. J Phys Chem B 2016; 120:10786-10796. [DOI: 10.1021/acs.jpcb.6b07205] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Caley Allen
- Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Robel Ghebreab
- Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Brian Doherty
- Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Bin Li
- Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
| | - Orlando Acevedo
- Department of Chemistry, University of Miami, Coral Gables, Florida 33146, United States
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11
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Ying A, Liu S, Li Z, Chen G, Yang J, Yan H, Xu S. Magnetic Nanoparticles-Supported Chiral Catalyst with an Imidazolium Ionic Moiety: An Efficient and Recyclable Catalyst for Asymmetric Michael and Aldol Reactions. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201600145] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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12
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Nagare AS, Manna A, Kumar A. Can a Diels–Alder reaction be accelerated in a supersaturated solvent at room temperature? NEW J CHEM 2016. [DOI: 10.1039/c6nj01912a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
New carbohydrate-based supersaturated solvent for superior rates and high product yields.
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Affiliation(s)
- Amit S. Nagare
- Physical and Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune 411008
- India
| | - Arpan Manna
- Physical and Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune 411008
- India
| | - Anil Kumar
- Physical and Materials Chemistry Division
- CSIR-National Chemical Laboratory
- Pune 411008
- India
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13
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Hubin PO, Jacquemin D, Leherte L, Vercauteren DP. Accessing the free energy profile of a ring closure in a proline-catalyzed reaction using a reactive force field. Theor Chem Acc 2015. [DOI: 10.1007/s00214-015-1792-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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14
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Meng J, Gao M, Lv H, Zhang X. Highly Enantioselective Hydrogenation of ο-Alkoxy Tetrasubstituted Enamides Catalyzed by a Rh/(R,S)-JosiPhos Catalyst. Org Lett 2015; 17:1842-5. [DOI: 10.1021/acs.orglett.5b00401] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Jingjing Meng
- College
of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei 430072, China
| | - Min Gao
- College
of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei 430072, China
| | - Hui Lv
- College
of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei 430072, China
| | - Xumu Zhang
- College
of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei 430072, China
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15
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Bandar JS, Barthelme A, Mazori AY, Lambert TH. Structure-Activity Relationship Studies of Cyclopropenimines as Enantioselective Brønsted Base Catalysts. Chem Sci 2015; 6:1537-1547. [PMID: 26504512 PMCID: PMC4618405 DOI: 10.1039/c4sc02402h] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Accepted: 11/19/2014] [Indexed: 11/21/2022] Open
Abstract
We recently demonstrated that chiral cyclopropenimines are viable Brønsted base catalysts in enantioselective Michael and Mannich reactions. Herein, we describe a series of structure-activity relationship studies that provide an enhanced understanding of the effectiveness of certain cyclopropenimines as enantioselective Brønsted base catalysts. These studies underscore the crucial importance of dicyclohexylamino substituents in mediating both reaction rate and enantioselectivity. In addition, an unusual catalyst CH···O interaction, which provides both ground state and transition state organization, is discussed. Cyclopropenimine stability studies have led to the identification of new catalysts with greatly improved stability. Finally, additional demonstrations of substrate scope and current limitations are provided herein.
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Affiliation(s)
- Jeffrey S. Bandar
- Department of Chemistry , Columbia University , 3000 Broadway , New York , NY 10027 , USA .
| | - Alexandre Barthelme
- Department of Chemistry , Columbia University , 3000 Broadway , New York , NY 10027 , USA .
| | - Alon Y. Mazori
- Department of Chemistry , Columbia University , 3000 Broadway , New York , NY 10027 , USA .
| | - Tristan H. Lambert
- Department of Chemistry , Columbia University , 3000 Broadway , New York , NY 10027 , USA .
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16
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Li X, Yang B, Jia X, Chen M, Hu Z. Temperature-responsive hairy particle-supported proline for direct asymmetric aldol reaction in water. RSC Adv 2015. [DOI: 10.1039/c5ra16393e] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
In this paper, three kinds of hairy particles with different brush structures were prepared and evaluated as chiral catalysts in the direct asymmetric aldol reaction.
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Affiliation(s)
- Xinjuan Li
- School of Chemistry and Chemical Engineering
- The Key Laboratory of Green Chemical Media and Reactions
- State Education Ministry of China
- Henan Normal University
- Xinxiang 453007
| | - Beilei Yang
- School of Chemistry and Chemical Engineering
- The Key Laboratory of Green Chemical Media and Reactions
- State Education Ministry of China
- Henan Normal University
- Xinxiang 453007
| | - Xianbin Jia
- School of Chemistry and Chemical Engineering
- The Key Laboratory of Green Chemical Media and Reactions
- State Education Ministry of China
- Henan Normal University
- Xinxiang 453007
| | - Maoqin Chen
- School of Chemistry and Chemical Engineering
- The Key Laboratory of Green Chemical Media and Reactions
- State Education Ministry of China
- Henan Normal University
- Xinxiang 453007
| | - Zhiguo Hu
- School of Chemistry and Chemical Engineering
- The Key Laboratory of Green Chemical Media and Reactions
- State Education Ministry of China
- Henan Normal University
- Xinxiang 453007
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17
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Acevedo O. Simulating chemical reactions in ionic liquids using QM/MM methodology. J Phys Chem A 2014; 118:11653-66. [PMID: 25329366 DOI: 10.1021/jp507967z] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The use of ionic liquids as a reaction medium for chemical reactions has dramatically increased in recent years due in large part to the numerous reported advances in catalysis and organic synthesis. In some extreme cases, ionic liquids have been shown to induce mechanistic changes relative to conventional solvents. Despite the large interest in the solvents, a clear understanding of the molecular factors behind their chemical impact is largely unknown. This feature article reviews our efforts developing and applying mixed quantum and molecular mechanical (QM/MM) methodology to elucidate the microscopic details of how these solvents operate to enhance rates and alter mechanisms for industrially and academically important reactions, e.g., Diels-Alder, Kemp eliminations, nucleophilic aromatic substitutions, and β-eliminations. Explicit solvent representation provided the medium dependence of the activation barriers and atomic-level characterization of the solute-solvent interactions responsible for the experimentally observed "ionic liquid effects". Technical advances are also discussed, including a linear-scaling pairwise electrostatic interaction alternative to Ewald sums, an efficient polynomial fitting method for modeling proton transfers, and the development of a custom ionic liquid OPLS-AA force field.
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Affiliation(s)
- Orlando Acevedo
- Department of Chemistry and Biochemistry, Auburn University , Auburn, Alabama 36849, United States
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18
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Yang X, Xue Y. Medium Effects on the 1,3-Dipolar Cycloaddition of Pyridazinium Dicyanomethanide with Ethyl Vinyl Ketone in Pure and Mixed Solvents from QM/MM Simulations. J Org Chem 2014; 79:4863-70. [DOI: 10.1021/jo500184f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xin Yang
- College of Chemistry, Key
Lab of Green Chemistry and Technology in Ministry of Education, Sichuan University, Chengdu 610064, People’s Republic of China
| | - Ying Xue
- College of Chemistry, Key
Lab of Green Chemistry and Technology in Ministry of Education, Sichuan University, Chengdu 610064, People’s Republic of China
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