1
|
Can Üsküp H, Yıldız T, Onar HÇ, Hasdemir B. Synthesis of Novel 1,4-Diketone Derivatives and Their Further Cyclization. ACS OMEGA 2023; 8:14047-14052. [PMID: 37091374 PMCID: PMC10116510 DOI: 10.1021/acsomega.3c00610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Accepted: 03/29/2023] [Indexed: 05/03/2023]
Abstract
One of the important reactions to obtain a new carbon-carbon bond is the Stetter reaction, which is generally via a nucleophilic catalyst like cyanide or thiazolium-NHC catalysts. In particular, 1,4-diketones with very functional properties are obtained by the Stetter reaction with the intermolecular reaction of an aldehyde and an α,β-unsaturated ketone. In this study, we synthesized new derivatives (substituted arenoxy) of 1,4-diketone compounds (2a-2n) with useful features by a new version of the Stetter reaction method. In our work, arenoxy benzaldehyde derivatives with different structures as the Michael donor and methyl vinyl ketone as the Michael acceptor were used for the intermolecular Stetter reaction. The reaction was catalyzed by 3-benzyl-5-(2-hydroxyethyl)-4-methylthiazolium chloride (3b), using triethylamine for the basic medium and dimethyl sulfoxide as the solvent. As a result, some novel arenoxy-substituted 1,4-diketones were gained with good yields at room temperature within 24 h through an intermolecular Stetter reaction. In addition, new furan and pyrrole derivatives were prepared by performing the cyclization reaction with one of the obtained new diketone compounds.
Collapse
Affiliation(s)
- Hacer Can Üsküp
- Department of Chemistry,
Organic Chemistry Division, Istanbul University-Cerrahpaşa, Avcilar, Istanbul 34320, Turkey
| | - Tülay Yıldız
- Department of Chemistry,
Organic Chemistry Division, Istanbul University-Cerrahpaşa, Avcilar, Istanbul 34320, Turkey
| | - Hülya Ç. Onar
- Department of Chemistry,
Organic Chemistry Division, Istanbul University-Cerrahpaşa, Avcilar, Istanbul 34320, Turkey
| | - Belma Hasdemir
- Department of Chemistry,
Organic Chemistry Division, Istanbul University-Cerrahpaşa, Avcilar, Istanbul 34320, Turkey
| |
Collapse
|
2
|
Zhang B, Yang G, Guo D, Wang J. Recent developments on NHC-driven dual catalytic approaches. Org Chem Front 2022. [DOI: 10.1039/d2qo00721e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
This article takes an in depth look at the early relay combination of NHC and other catalysts, and the latest progress in dual catalysis, analyzing the breakthroughs and limitations.
Collapse
Affiliation(s)
- Bei Zhang
- College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241002, China
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, 100084, China
| | - Gongming Yang
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, 100084, China
| | - Donghui Guo
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, 100084, China
| | - Jian Wang
- College of Chemistry and Materials Science, Anhui Normal University, Wuhu 241002, China
- School of Pharmaceutical Sciences, Tsinghua University, Beijing, 100084, China
| |
Collapse
|
3
|
Ghanbari H, Robertson KN, Clyburne J, Soleimani E. Betaine formation from the reactions of N-heterocyclic carbenes with polarized alkenes. CAN J CHEM 2021. [DOI: 10.1139/cjc-2021-0234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
N-heterocyclic carbenes [1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene 1a (IMes) or 1,3-bis(2,6-di-iso-propylphenyl)imidazolidene 1b (SIPr)] react with the polarized alkenes 2 and 4 to form the crystalline betaines 3a, 3b and 5a. Furthermore, a one-pot reaction between an aldehyde, malonitrile, and an imidazolium salt of an N-heterocyclic carbene has been developed for the efficient preparation of betaine 5a without isolation of the free carbene. Full characterization data, including X-ray crystal structures, is reported for the three synthesized betaines. The structures of the betaines 3a, 3b and 5a shed new light on the initial products formed in the reactions between N-heterocyclic carbenes and compounds containing polarized double bonds.
Collapse
Affiliation(s)
- Hamed Ghanbari
- Razi University, 48494, Department of Chemistry, Kermanshah, Iran (the Islamic Republic of)
| | - Katherine N. Robertson
- Saint Mary's University, Chemistry, 923 Robie Street, Halifax, Nova Scotia, Canada, B3H 3C3
| | - Jason Clyburne
- Saint Mary’s University, Department of Chemistry, Halifax, Canada, B3H 3C3
| | - Ebrahim Soleimani
- Razi University, 48494, Department of Chemistry, Kermanshah, Iran (the Islamic Republic of)
- Saint Mary’s University, Department of Chemistry, Halifax, Canada, B3H 3C3
- Dalhousie University, 3688, Department of Chemistry, Halifax, Canada, B3H 4R2
| |
Collapse
|
4
|
Pearl ES, Fellner DMJ, Söhnel T, Furkert DP, Brimble MA. A Highly Efficient
N
‐Mesityl Thiazolylidene for the Aliphatic Stetter Reaction: Stereoelectronic Quantification for Comparison of N‐Heterocyclic Carbene Organocatalysts. ASIAN J ORG CHEM 2021. [DOI: 10.1002/ajoc.202100445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Esperanza S. Pearl
- School of Chemical Sciences The University of Auckland 23 Symonds St Auckland 1010 New Zealand
| | - Daniel M. J. Fellner
- School of Chemical Sciences The University of Auckland 23 Symonds St Auckland 1010 New Zealand
| | - Tilo Söhnel
- School of Chemical Sciences The University of Auckland 23 Symonds St Auckland 1010 New Zealand
| | - Daniel P. Furkert
- School of Chemical Sciences The University of Auckland 23 Symonds St Auckland 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery 3 Symonds St Auckland 1010 New Zealand
| | - Margaret A. Brimble
- School of Chemical Sciences The University of Auckland 23 Symonds St Auckland 1010 New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery 3 Symonds St Auckland 1010 New Zealand
| |
Collapse
|
5
|
Delany EG, Connon SJ. Enantioselective N-heterocyclic carbene-catalysed intermolecular crossed benzoin condensations: improved catalyst design and the role of in situ racemisation. Org Biomol Chem 2021; 19:248-258. [PMID: 33289760 DOI: 10.1039/d0ob02017f] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The enantioselective intermolecular crossed-benzoin condensation mediated by novel chiral N-heterocyclic carbenes derived from pyroglutamic acid has been investigated. A small library of chiral triazolium ions were synthesised. Each possessed a tertiary alcohol H-bond donor and a variable N-aryl substituent. It was found that increasing both the steric requirement and the electron-withdrawing characteristics of the N-aryl ring led to more chemoselective, efficient and enantioselective chemistry, however both quenching the reaction at different times and deuterium incorporation experiments involving the product revealed that this is complicated by product racemisation in situ (except in the case of benzoin itself), which explains the dependence of enantioselectivity on the electrophilicity of the reacting aldehydes common in the literature. Subsequent protocol optimisation, where one reacting partner was an o-substituted benzaldehyde, allowed a range of crossed-benzoins to be synthesised in moderate-good yields with moderate to excellent enantioselectivity.
Collapse
Affiliation(s)
- Eoghan G Delany
- Centre for Synthesis and Chemical Biology, Trinity Biomedical Sciences Institute, School of Chemistry, The University of Dublin, Trinity College, Dublin 2, Ireland.
| | | |
Collapse
|
6
|
|
7
|
Kyan R, Sato K, Mase N, Narumi T. Pendant Alkoxy Groups on N-Aryl Substitutions Drive the Efficiency of Imidazolylidene Catalysts for Homoenolate Annulation from Enal and Aldehyde. Angew Chem Int Ed Engl 2020; 59:19031-19036. [PMID: 32662539 DOI: 10.1002/anie.202008631] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Indexed: 01/03/2023]
Abstract
Hydrogen-transfer in the tetrahedral intermediate generated from an imidazolylidene catalyst and α,β-unsaturated aldehyde forms a conjugated Breslow intermediate. This is a critical step affecting the efficiency of the NHC-catalyzed γ-butyrolactone formation via homoenolate addition to aryl aldehydes. A novel type of imidazolylidene catalyst with pendant alkoxy groups on the ortho-N-aryl groups is described. Catalyst of this sort facilitates the formation of the conjugated Breslow intermediate. Studies of the rate constants for homoenolate annulation affording γ-butyrolactones, reveal that introduction of the oxygen atoms in the appropriate position of the N-aryl substituents can increase the efficiency of imidazolylidene catalysts. Structural and mechanistic studies revealed that pendant alkoxy groups can be located close to the proton of the tetrahedral intermediate, thereby facilitating the proton transfer.
Collapse
Affiliation(s)
- Ryuji Kyan
- Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561, Shizuoka, Japan
| | - Kohei Sato
- Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, Shizuoka University, Japan.,Course of Applied Chemistry and Biochemical Engineering, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Japan
| | - Nobuyuki Mase
- Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561, Shizuoka, Japan.,Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, Shizuoka University, Japan.,Course of Applied Chemistry and Biochemical Engineering, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Japan.,Research Institute of Green Science and Technology, Shizuoka University, Japan
| | - Tetsuo Narumi
- Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561, Shizuoka, Japan.,Department of Applied Chemistry and Biochemical Engineering, Faculty of Engineering, Shizuoka University, Japan.,Course of Applied Chemistry and Biochemical Engineering, Department of Engineering, Graduate School of Integrated Science and Technology, Shizuoka University, Japan.,Research Institute of Green Science and Technology, Shizuoka University, Japan
| |
Collapse
|
8
|
Kyan R, Sato K, Mase N, Narumi T. Pendant Alkoxy Groups on N‐Aryl Substitutions Drive the Efficiency of Imidazolylidene Catalysts for Homoenolate Annulation from Enal and Aldehyde. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ryuji Kyan
- Graduate School of Science and Technology Shizuoka University 3-5-1 Johoku Hamamatsu 432-8561 Shizuoka Japan
| | - Kohei Sato
- Department of Applied Chemistry and Biochemical Engineering Faculty of Engineering Shizuoka University Japan
- Course of Applied Chemistry and Biochemical Engineering Department of Engineering Graduate School of Integrated Science and Technology Shizuoka University Japan
| | - Nobuyuki Mase
- Graduate School of Science and Technology Shizuoka University 3-5-1 Johoku Hamamatsu 432-8561 Shizuoka Japan
- Department of Applied Chemistry and Biochemical Engineering Faculty of Engineering Shizuoka University Japan
- Course of Applied Chemistry and Biochemical Engineering Department of Engineering Graduate School of Integrated Science and Technology Shizuoka University Japan
- Research Institute of Green Science and Technology Shizuoka University Japan
| | - Tetsuo Narumi
- Graduate School of Science and Technology Shizuoka University 3-5-1 Johoku Hamamatsu 432-8561 Shizuoka Japan
- Department of Applied Chemistry and Biochemical Engineering Faculty of Engineering Shizuoka University Japan
- Course of Applied Chemistry and Biochemical Engineering Department of Engineering Graduate School of Integrated Science and Technology Shizuoka University Japan
- Research Institute of Green Science and Technology Shizuoka University Japan
| |
Collapse
|
9
|
Iwai K, Ono M, Nanjo Y, Ema T. Minimization of Amounts of Catalyst and Solvent in NHC-Catalyzed Benzoin Reactions of Solid Aldehydes: Mechanistic Consideration of Solid-to-Solid Conversion and Total Synthesis of Isodarparvinol B. ACS OMEGA 2020; 5:10207-10216. [PMID: 32391509 PMCID: PMC7203951 DOI: 10.1021/acsomega.0c01141] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 04/08/2020] [Indexed: 05/03/2023]
Abstract
Attempts were made to minimize the amounts of catalyst and solvent in the NHC-catalyzed benzoin reactions of solid aldehydes. In some case, solid-to-solid conversions proceeded in the solvent-free NHC-catalyzed benzoin reactions. Even if a mixture of the substrate, N-heterocyclic carbene (NHC) precursor, and inorganic base was initially a powdery solid, the reaction did proceed at reaction temperature lower than the melting points of each compound. The solid mixture partially melted or became a slurry or suspension in the meantime. We call this solid/liquid mixture a semisolid state. The reaction giving an optically active product was faster than that giving a racemic mixture of the same product. Melting-point depression was observed for a series of mixtures of the substrate and product in different substrate/product ratios. Solvent-free solid-to-solid conversions were accelerated by the formation of a semisolid state resulting from the melting-point depression of the solid substrate accompanied by the product formation. In the case of solid substrates with high melting points, melting-point depression was useless, and the addition of a small amount of solvent was needed. The first total synthesis of isodarparvinol B was achieved via the NHC-catalyzed intramolecular benzoin reaction using a small amount of solvent as an additive.
Collapse
|
10
|
Li J, Duan X, Tian Z, Zheng Y, Qi J. N‐Heterocyclic Carbene‐Catalyzed Activation of Ynals for the Construction of Functional Pyridines. ASIAN J ORG CHEM 2020. [DOI: 10.1002/ajoc.201900693] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Jia‐Hui Li
- Key Laboratory of Chemical Biology of Hebei ProvinceCollege of Chemistry and Environmental ScienceHebei University Baoding 071002 Hebei Province People's Republic of China
| | - Xiao‐Yong Duan
- Key Laboratory of Chemical Biology of Hebei ProvinceCollege of Chemistry and Environmental ScienceHebei University Baoding 071002 Hebei Province People's Republic of China
- Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationHebei University Baoding 071002 Hebei Province People's Republic of China
| | - Zhao‐Hui Tian
- Key Laboratory of Chemical Biology of Hebei ProvinceCollege of Chemistry and Environmental ScienceHebei University Baoding 071002 Hebei Province People's Republic of China
| | - Yi‐Fan Zheng
- Key Laboratory of Chemical Biology of Hebei ProvinceCollege of Chemistry and Environmental ScienceHebei University Baoding 071002 Hebei Province People's Republic of China
| | - Jing Qi
- Key Laboratory of Chemical Biology of Hebei ProvinceCollege of Chemistry and Environmental ScienceHebei University Baoding 071002 Hebei Province People's Republic of China
- Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationHebei University Baoding 071002 Hebei Province People's Republic of China
| |
Collapse
|
11
|
Shyam A, Mondal P. Theoretical Insight towards Mechanism, Role of NHC and DBU in the Synthesis of Substituted Quinolines. ChemistrySelect 2020. [DOI: 10.1002/slct.201903697] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Abhijit Shyam
- Department of ChemistryAssam University, Silchar, Silchar Assam 788011 India
| | - Paritosh Mondal
- Department of ChemistryAssam University, Silchar, Silchar Assam 788011 India
| |
Collapse
|
12
|
Shi X, Dong M, Duan X, Cao T, Qi J. N
‐Heterocyclic Carbene Catalyzed [3+2] Cycloaddition of Enals with
β,γ
‐Unsaturated
α
‐Ketimino Esters for the Synthesis of Multisubstituted Cyclopentanone. Adv Synth Catal 2020. [DOI: 10.1002/adsc.201901144] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Xiao‐Qian Shi
- Key Laboratory of Chemical Biology of Hebei Province, College of Chemistry and Environmental ScienceHebei University
| | - Meng‐Die Dong
- Key Laboratory of Chemical Biology of Hebei Province, College of Chemistry and Environmental ScienceHebei University
| | - Xiao‐Yong Duan
- Key Laboratory of Chemical Biology of Hebei Province, College of Chemistry and Environmental ScienceHebei University
- Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationHebei University
| | - Teng‐Liang Cao
- Key Laboratory of Chemical Biology of Hebei Province, College of Chemistry and Environmental ScienceHebei University
| | - Jing Qi
- Key Laboratory of Chemical Biology of Hebei Province, College of Chemistry and Environmental ScienceHebei University
- Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationHebei University
| |
Collapse
|
13
|
Balanna K, Madica K, Mukherjee S, Ghosh A, Poisson T, Besset T, Jindal G, Biju AT. N-Heterocyclic Carbene-Catalyzed Formal [6+2] Annulation Reaction via Cross-Conjugated Aza-Trienolate Intermediates. Chemistry 2019; 26:818-822. [PMID: 31765059 DOI: 10.1002/chem.201905177] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Indexed: 01/17/2023]
Abstract
The diverse reactivity of N-heterocyclic carbenes (NHCs) in organocatalysis is due to the possibility of different modes of action. Although NHC-bound enolates and dienolates are known, the related NHC-bound cross-conjugated aza-trienolates remain elusive. Herein, we demonstrate the NHC-catalyzed formal [6+2] annulation of nitrogen-containing heterocyclic aldehydes with α,α,α-trifluoroacetophenones leading to the formation of versatile pyrrolooxazolones (29 examples). The catalytically generated cross-conjugated aza-trienolates (aza-fulvene type) underwent smooth [6+2] annulation with electrophilic ketones to afford the product in moderate to good yields under mild conditions. Preliminary DFT studies on the mechanism are also provided.
Collapse
Affiliation(s)
- Kuruva Balanna
- Department of Organic Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Krishnaprasad Madica
- Department of Organic Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Subrata Mukherjee
- Department of Organic Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Arghya Ghosh
- Department of Organic Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Thomas Poisson
- Institut Universitaire de France, 1 rue Descartes, 75231, Paris, France.,INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), Normandie Univ, 76000, Rouen, France
| | - Tatiana Besset
- INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), Normandie Univ, 76000, Rouen, France
| | - Garima Jindal
- Department of Organic Chemistry, Indian Institute of Science, Bangalore, 560012, India
| | - Akkattu T Biju
- Department of Organic Chemistry, Indian Institute of Science, Bangalore, 560012, India
| |
Collapse
|
14
|
Zhao JJ, Zhang HH, Shen X, Yu S. Enantioselective Radical Hydroacylation of Enals with α-Ketoacids Enabled by Photoredox/Amine Cocatalysis. Org Lett 2019; 21:913-916. [DOI: 10.1021/acs.orglett.8b03840] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Jia-Jia Zhao
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Hong-Hao Zhang
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Xu Shen
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Shouyun Yu
- State Key Laboratory of Analytical Chemistry for Life Science, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| |
Collapse
|
15
|
Maguire AC, Kumar V, Connon SJ. Highly chemoselective, sterically sensitive NHC-catalysed amine acylation with pyridil. Chem Commun (Camb) 2019; 55:13526-13529. [DOI: 10.1039/c9cc06937b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new strategy for the protection of amines has been developed involving reaction with pyridil under the influence of N-heterocyclic carbene catalysis.
Collapse
Affiliation(s)
- Amy C. Maguire
- School of Chemistry Trinity Biomedical Sciences Institute
- Trinity College Dublin
- Dublin 2
- Ireland
| | - Vikas Kumar
- School of Chemistry Trinity Biomedical Sciences Institute
- Trinity College Dublin
- Dublin 2
- Ireland
| | - Stephen J. Connon
- School of Chemistry Trinity Biomedical Sciences Institute
- Trinity College Dublin
- Dublin 2
- Ireland
| |
Collapse
|
16
|
Xu J, Peng J, He C, Ren H. N-Heterocyclic carbene catalyzed chemo- and enantioselective cross-benzoin reaction of aldehydes with isatins. Org Chem Front 2019. [DOI: 10.1039/c8qo01085d] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A highly chemoselective N-heterocyclic carbene catalyzed intermolecular cross-benzoin reaction of aldehydes with isatins to afford enantioenriched 3-substituted-3-hydroxyoxindoles is described.
Collapse
Affiliation(s)
- Jianfeng Xu
- Department of Chemistry
- Zhejiang Sci-Tech University
- Hangzhou 310018
- People's Republic of China
| | - Jingyi Peng
- Department of Chemistry
- Zhejiang Sci-Tech University
- Hangzhou 310018
- People's Republic of China
| | - Chonglong He
- Department of Chemistry
- Zhejiang Sci-Tech University
- Hangzhou 310018
- People's Republic of China
| | - Hongjun Ren
- Department of Chemistry
- Zhejiang Sci-Tech University
- Hangzhou 310018
- People's Republic of China
| |
Collapse
|
17
|
Bie J, Lang M, Wang J. Enantioselective N-Heterocyclic Carbene-Catalyzed Kinetic Resolution of Anilides. Org Lett 2018; 20:5866-5871. [PMID: 30188132 DOI: 10.1021/acs.orglett.8b02538] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The N-heterocyclic carbene (NHC)-catalyzed enantioselective kinetic resolution of anilides (a kind of hemiaminals) is reported. Upon exposure to the reaction in the presence of an NHC precatalyst and base, catalytic C-O bond formation occurs, providing axially chiral isoindolinones in high yields with excellent enantioselectivities.
Collapse
Affiliation(s)
- Jianbo Bie
- School of Pharmaceutical Sciences, Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education) , Tsinghua University , Beijing , 100084 , China
| | - Ming Lang
- School of Pharmaceutical Sciences, Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education) , Tsinghua University , Beijing , 100084 , China
| | - Jian Wang
- School of Pharmaceutical Sciences, Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education) , Tsinghua University , Beijing , 100084 , China
| |
Collapse
|
18
|
Mukherjee S, Biju AT. Recent Advances in the Organocatalytic Enantioselective Synthesis of Functionalized β-Lactones. Chem Asian J 2018; 13:2333-2349. [DOI: 10.1002/asia.201800902] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Revised: 07/20/2018] [Indexed: 01/25/2023]
Affiliation(s)
- Subrata Mukherjee
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune 411008 India
| | - Akkattu T. Biju
- Department of Organic Chemistry; Indian Institute of Science; Bangalore 560012 India
| |
Collapse
|
19
|
Lang M, Wang J. N-Heterocyclic Carbene-Catalyzed Enantioselective β-Amination of α-Bromoenals Enabled by a Proton-Shuttling Strategy. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800648] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Ming Lang
- School of Pharmaceutical Sciences; Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education); Tsinghua University; 100084 Beijing China
| | - Jian Wang
- School of Pharmaceutical Sciences; Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education); Tsinghua University; 100084 Beijing China
| |
Collapse
|
20
|
|
21
|
Ahire MM, Mhaske SB. Isa‒NHC‒catalyzed intermolecular Stetter reaction of aromatic aldehydes with maleimides: An efficient access to 3‒aroylsuccinimides. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.03.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
22
|
Zhao C, Guo D, Munkerup K, Huang KW, Li F, Wang J. Enantioselective [3+3] atroposelective annulation catalyzed by N-heterocyclic carbenes. Nat Commun 2018; 9:611. [PMID: 29426851 PMCID: PMC5807440 DOI: 10.1038/s41467-018-02952-3] [Citation(s) in RCA: 90] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Accepted: 01/09/2018] [Indexed: 11/09/2022] Open
Abstract
Axially chiral molecules are among the most valuable substrates in organic synthesis. They are typically used as chiral ligands or catalysts in asymmetric reactions. Recent progress for the construction of these chiral molecules is mainly focused on the transition-metal-catalyzed transformations. Here, we report the enantioselective NHC-catalyzed (NHC: N-heterocyclic carbenes) atroposelective annulation of cyclic 1,3-diones with ynals. In the presence of NHC precatalyst, base, Lewis acid and oxidant, a catalytic C-C bond formation occurs, providing axially chiral α-pyrone-aryls in moderate to good yields and with high enantioselectivities. Control experiments indicated that alkynyl acyl azoliums, acting as active intermediates, are employed to atroposelectively assemble chiral biaryls and such a methodology may be creatively applied to other useful NHC-catalyzed asymmetric transformations.
Collapse
Affiliation(s)
- Changgui Zhao
- School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology (Ministry of Education), Tsinghua University Beijing, 100084, Beijing, China
| | - Donghui Guo
- School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology (Ministry of Education), Tsinghua University Beijing, 100084, Beijing, China
| | - Kristin Munkerup
- Division of Chemical and Life Sciences & Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Kuo-Wei Huang
- Division of Chemical and Life Sciences & Engineering and KAUST Catalysis Center, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia
| | - Fangyi Li
- School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology (Ministry of Education), Tsinghua University Beijing, 100084, Beijing, China
| | - Jian Wang
- School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Key Laboratory of Bioorganic Phosphorous Chemistry and Chemical Biology (Ministry of Education), Tsinghua University Beijing, 100084, Beijing, China.
| |
Collapse
|
23
|
Patra A, Gelat F, Pannecoucke X, Poisson T, Besset T, Biju AT. Synthesis of 4-Difluoromethylquinolines by NHC-Catalyzed Umpolung of Imines. Org Lett 2018; 20:1086-1089. [DOI: 10.1021/acs.orglett.7b04055] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Atanu Patra
- Organic
Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi
Bhabha Road, Pune 411008, India
- Academy of Scientific and Innovative Research (AcSIR), New Delhi 110020, India
| | - Fabien Gelat
- Normandie Université,
INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
| | - Xavier Pannecoucke
- Normandie Université,
INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
| | - Thomas Poisson
- Normandie Université,
INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
- Institut Universitaire de France, 103 boulevard Saint-Michel, 75005 Paris, France
| | - Tatiana Besset
- Normandie Université,
INSA Rouen, UNIROUEN, CNRS, COBRA (UMR 6014), 76000 Rouen, France
| | - Akkattu T. Biju
- Organic
Chemistry Division, CSIR-National Chemical Laboratory, Dr. Homi
Bhabha Road, Pune 411008, India
| |
Collapse
|
24
|
Krishnan J, Jose A, Sasidhar BS, Suresh E, Menon RS, Nair V. An uncommon multicomponent reaction involving nucleophilic heterocyclic carbenes: facile synthesis of fully substituted cyclopentanones. Org Chem Front 2018. [DOI: 10.1039/c7qo01051f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An unprecedented three component reaction involving arylidene oxazolone, enal and NHC, leading to the synthesis of fully substituted cyclopentanone derivatives with three contiguous stereocenters, is reported.
Collapse
Affiliation(s)
- Jagadeesh Krishnan
- Chemical Sciences and Technology Division
- National Institute for Interdisciplinary Science and Technology (CSIR-NIIST)
- Thiruvananthapuram – 695 019
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - Anu Jose
- Chemical Sciences and Technology Division
- National Institute for Interdisciplinary Science and Technology (CSIR-NIIST)
- Thiruvananthapuram – 695 019
- India
| | - B. S. Sasidhar
- Chemical Sciences and Technology Division
- National Institute for Interdisciplinary Science and Technology (CSIR-NIIST)
- Thiruvananthapuram – 695 019
- India
- Academy of Scientific and Innovative Research (AcSIR)
| | - E. Suresh
- Analytical Department and Centralized Instrument Facility
- CSIR-CSMCRI
- Bhavnagar – 364 002
- India
| | - Rajeev S. Menon
- Department of Chemistry
- Central University of Haryana
- Mahendergarh
- India
| | - Vijay Nair
- Chemical Sciences and Technology Division
- National Institute for Interdisciplinary Science and Technology (CSIR-NIIST)
- Thiruvananthapuram – 695 019
- India
| |
Collapse
|
25
|
Delany EG, Connon SJ. Highly chemoselective intermolecular cross-benzoin reactions using an ad hoc designed novel N-heterocyclic carbene catalyst. Org Biomol Chem 2018; 16:780-786. [DOI: 10.1039/c7ob03005c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new N-heterocyclic carbene catalyst incorporating a bulky yet electron-deficient N-aryl substituent promotes highly chemoselective intermolecular crossed benzoin condensations.
Collapse
Affiliation(s)
- Eoghan G. Delany
- School of Chemistry Trinity Biomedical Sciences Institute
- Trinity College Dublin
- Dublin 2
- Ireland
| | - Stephen J. Connon
- School of Chemistry Trinity Biomedical Sciences Institute
- Trinity College Dublin
- Dublin 2
- Ireland
| |
Collapse
|
26
|
Tu PC, Zhou L, Kirillov AM, Fang R, Yang L. Computational study on the NHC-catalyzed synthesis of 2,3-disubstituted indoles: mechanism, key intermediate and the role of the catalyst. Org Chem Front 2018. [DOI: 10.1039/c8qo00139a] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Mechanism, key intermediate and role of NHC for NHC-catalyzed umpolung of imines are clarified through our calculations.
Collapse
Affiliation(s)
- Peng-Cheng Tu
- State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
- P. R. China
| | - Lin Zhou
- State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
- P. R. China
| | - Alexander M. Kirillov
- Centro de Química Estrutural
- Complexo I
- Instituto Superior Técnico
- Universidade de Lisboa
- Lisbon
| | - Ran Fang
- State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
- P. R. China
| | - Lizi Yang
- State Key Laboratory of Applied Organic Chemistry and Key Laboratory of Nonferrous Metals Chemistry and Resources Utilization of Gansu Province
- College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou 730000
- P. R. China
| |
Collapse
|
27
|
Liu J, Das DK, Zhang G, Yang S, Zhang H, Fang X. N-Heterocyclic Carbene-Catalyzed Umpolung of β,γ-Unsaturated 1,2-Diketones. Org Lett 2017; 20:64-67. [DOI: 10.1021/acs.orglett.7b03358] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jian Liu
- College
of Chemistry, Fuzhou University, Fuzhou, 350116, China
| | - Deb Kumar Das
- State
Key Laboratory of Structural Chemistry, Center for Excellence in Molecular
Synthesis, Fujian Institute of Research on the Structure of Matter, University of Chinese Academy of Sciences, Fuzhou, 350100, China
| | - Guoxiang Zhang
- State
Key Laboratory of Structural Chemistry, Center for Excellence in Molecular
Synthesis, Fujian Institute of Research on the Structure of Matter, University of Chinese Academy of Sciences, Fuzhou, 350100, China
| | - Shuang Yang
- State
Key Laboratory of Structural Chemistry, Center for Excellence in Molecular
Synthesis, Fujian Institute of Research on the Structure of Matter, University of Chinese Academy of Sciences, Fuzhou, 350100, China
| | - Hao Zhang
- State
Key Laboratory of Structural Chemistry, Center for Excellence in Molecular
Synthesis, Fujian Institute of Research on the Structure of Matter, University of Chinese Academy of Sciences, Fuzhou, 350100, China
| | - Xinqiang Fang
- State
Key Laboratory of Structural Chemistry, Center for Excellence in Molecular
Synthesis, Fujian Institute of Research on the Structure of Matter, University of Chinese Academy of Sciences, Fuzhou, 350100, China
| |
Collapse
|
28
|
Maji B. N-Heterocyclic-Carbene-Catalyzed Reactions of Nitroalkenes: Synthesizing Important Building Blocks. ASIAN J ORG CHEM 2017. [DOI: 10.1002/ajoc.201700520] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Biswajit Maji
- Department of Chemistry; Indira Gandhi National Tribal University; Anuppur Amarkantak Madhya Pradesh 484887 India
| |
Collapse
|
29
|
Wu Z, Wang J. Enantioselective Medium-Ring Lactone Synthesis through an NHC-Catalyzed Intramolecular Desymmetrization of Prochiral 1,3-Diols. ACS Catal 2017. [DOI: 10.1021/acscatal.7b02302] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Zijun Wu
- School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| | - Jian Wang
- School of Pharmaceutical Sciences, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, Key Laboratory of Bioorganic Phosphorous Chemistry & Chemical Biology (Ministry of Education), Tsinghua University, Beijing 100084, China
| |
Collapse
|
30
|
Li Z, Li X, Cheng JP. An Acidity Scale of Triazolium-Based NHC Precursors in DMSO. J Org Chem 2017; 82:9675-9681. [DOI: 10.1021/acs.joc.7b01755] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhen Li
- State Key Laboratory of Elemento-Organic
Chemistry, College of Chemistry, Collaborative Innovation Center of
Chemical Science and Engineering, Nankai University, Tianjin 300071, China
| | - Xin Li
- State Key Laboratory of Elemento-Organic
Chemistry, College of Chemistry, Collaborative Innovation Center of
Chemical Science and Engineering, Nankai University, Tianjin 300071, China
| | - Jin-Pei Cheng
- State Key Laboratory of Elemento-Organic
Chemistry, College of Chemistry, Collaborative Innovation Center of
Chemical Science and Engineering, Nankai University, Tianjin 300071, China
| |
Collapse
|
31
|
Das TK, Biju AT. A Method for the Analysis of Free Carbenes Present after NHC-Organocatalyzed Transformations. European J Org Chem 2017. [DOI: 10.1002/ejoc.201700903] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Tamal Kanti Das
- Organic Chemistry Division; CSIR National Chemical Laboratory; Dr. Homi Bhabha Road 411008 Pune Maharashtra India
- Academy of Scientific and Innovative Research (AcSIR); 110020 New Delhi India
| | - Akkattu T. Biju
- Organic Chemistry Division; CSIR National Chemical Laboratory; Dr. Homi Bhabha Road 411008 Pune Maharashtra India
- Academy of Scientific and Innovative Research (AcSIR); 110020 New Delhi India
| |
Collapse
|
32
|
Zhang C, Lupton DW. Enantioselective N-Heterocyclic Carbene Catalyzed Synthesis of Functionalized Indenes. Org Lett 2017; 19:4456-4459. [PMID: 28812898 DOI: 10.1021/acs.orglett.7b01981] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
An enantioselective NHC (N-heterocyclic carbene) catalyzed synthesis of indenes from bifunctional α,β-unsaturated acyl fluorides and TMS enol ethers has been discovered. The reaction has broad generality (31 examples) and proceeds with high levels of enantioselectivity (most >92:8 er). Mechanistically the reaction likely occurs via a Michael/β-lactonization/decarboxylation sequence. Derivatization studies and limitations are discussed.
Collapse
Affiliation(s)
- Changhe Zhang
- School of Chemistry, Monash University , Clayton 3800, Victoria, Australia
| | - David W Lupton
- School of Chemistry, Monash University , Clayton 3800, Victoria, Australia
| |
Collapse
|
33
|
Kong X, Zhang G, Yang S, Liu X, Fang X. N-Heterocyclic Carbene-Catalyzed Umpolung of Alkynyl 1,2-Diketones. Adv Synth Catal 2017. [DOI: 10.1002/adsc.201700700] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Xiangwen Kong
- Liaoning University; Shenyang 110036 People's Republic of China
| | - Guoxiang Zhang
- College of Chemistry; Fuzhou University; Fuzhou 350116 People's Republic of China
| | - Shuang Yang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter; Chinese Academy of Sciences; Fuzhou 350100 People's Republic of China
| | - Xiaozhi Liu
- Liaoning University; Shenyang 110036 People's Republic of China
| | - Xinqiang Fang
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter; Chinese Academy of Sciences; Fuzhou 350100 People's Republic of China
| |
Collapse
|
34
|
Li XS, Zhao LL, Wang XK, Cao L, Shi XQ, Zhang R, Qi J. Enantioselective [3 + 2] Annulation of Enals with 2-Aminoacrylates Catalyzed by N-Heterocyclic Carbene. Org Lett 2017; 19:3943-3946. [DOI: 10.1021/acs.orglett.7b01860] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xing-Shuo Li
- Key Laboratory of Chemical Biology of Hebei Province, College of
Chemistry and Environmental Science, and ‡Key Laboratory of Medicinal Chemistry
and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, People’s Republic of China
| | - Liang-Liang Zhao
- Key Laboratory of Chemical Biology of Hebei Province, College of
Chemistry and Environmental Science, and ‡Key Laboratory of Medicinal Chemistry
and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, People’s Republic of China
| | - Xiao-Ke Wang
- Key Laboratory of Chemical Biology of Hebei Province, College of
Chemistry and Environmental Science, and ‡Key Laboratory of Medicinal Chemistry
and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, People’s Republic of China
| | - Li−Li Cao
- Key Laboratory of Chemical Biology of Hebei Province, College of
Chemistry and Environmental Science, and ‡Key Laboratory of Medicinal Chemistry
and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, People’s Republic of China
| | - Xiao-Qian Shi
- Key Laboratory of Chemical Biology of Hebei Province, College of
Chemistry and Environmental Science, and ‡Key Laboratory of Medicinal Chemistry
and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, People’s Republic of China
| | - Rui Zhang
- Key Laboratory of Chemical Biology of Hebei Province, College of
Chemistry and Environmental Science, and ‡Key Laboratory of Medicinal Chemistry
and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, People’s Republic of China
| | - Jing Qi
- Key Laboratory of Chemical Biology of Hebei Province, College of
Chemistry and Environmental Science, and ‡Key Laboratory of Medicinal Chemistry
and Molecular Diagnosis of the Ministry of Education, Hebei University, Baoding 071002, People’s Republic of China
| |
Collapse
|
35
|
Asymmetric cross-benzoin condensation promoted by a chiral triazolium precatalyst bearing a pyridine moiety. Tetrahedron 2017. [DOI: 10.1016/j.tet.2017.05.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
|
36
|
Kyan R, Sato K, Mase N, Watanabe N, Narumi T. Tuning the Catalyst Reactivity of Imidazolylidene Catalysts through Substituent Effects on the N-Aryl Groups. Org Lett 2017; 19:2750-2753. [DOI: 10.1021/acs.orglett.7b01105] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ryuji Kyan
- Department of Engineering, Graduate School of Integrated Science
and Technology, ‡Research Institute of Green Science and Technology,
and §Graduate School of
Science and Technology, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561 Shizuoka, Japan
| | - Kohei Sato
- Department of Engineering, Graduate School of Integrated Science
and Technology, ‡Research Institute of Green Science and Technology,
and §Graduate School of
Science and Technology, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561 Shizuoka, Japan
| | - Nobuyuki Mase
- Department of Engineering, Graduate School of Integrated Science
and Technology, ‡Research Institute of Green Science and Technology,
and §Graduate School of
Science and Technology, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561 Shizuoka, Japan
| | - Naoharu Watanabe
- Department of Engineering, Graduate School of Integrated Science
and Technology, ‡Research Institute of Green Science and Technology,
and §Graduate School of
Science and Technology, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561 Shizuoka, Japan
| | - Tetsuo Narumi
- Department of Engineering, Graduate School of Integrated Science
and Technology, ‡Research Institute of Green Science and Technology,
and §Graduate School of
Science and Technology, Shizuoka University, 3-5-1 Johoku, Hamamatsu, 432-8561 Shizuoka, Japan
| |
Collapse
|
37
|
Selg C, Neumann W, Lönnecke P, Hey-Hawkins E, Zeitler K. Carboranes as Aryl Mimetics in Catalysis: A Highly Active Zwitterionic NHC-Precatalyst. Chemistry 2017; 23:7932-7937. [DOI: 10.1002/chem.201700209] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2017] [Indexed: 01/12/2023]
Affiliation(s)
- Christoph Selg
- Institut für Organische Chemie; Universität Leipzig; Johannisallee 29 04103 Leipzig Germany
| | - Wilma Neumann
- Institut für Anorganische Chemie; Universität Leipzig; Johannisallee 29 04103 Leipzig Germany
- Current address: Department of Chemistry; Massachusetts Institute of Technology; 77 Massachusetts Avenue Cambridge MA 02139 USA
| | - Peter Lönnecke
- Institut für Anorganische Chemie; Universität Leipzig; Johannisallee 29 04103 Leipzig Germany
| | - Evamarie Hey-Hawkins
- Institut für Anorganische Chemie; Universität Leipzig; Johannisallee 29 04103 Leipzig Germany
| | - Kirsten Zeitler
- Institut für Organische Chemie; Universität Leipzig; Johannisallee 29 04103 Leipzig Germany
| |
Collapse
|
38
|
Janssen-Müller D, Singha S, Lied F, Gottschalk K, Glorius F. NHC-organokatalysierte CAr
-O-Bindungsspaltung: milder Zugang zu 2-Hydroxybenzophenonen. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201610203] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Daniel Janssen-Müller
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstraße 40 48149 Münster Deutschland
| | - Santanu Singha
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstraße 40 48149 Münster Deutschland
| | - Fabian Lied
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstraße 40 48149 Münster Deutschland
| | - Karin Gottschalk
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstraße 40 48149 Münster Deutschland
| | - Frank Glorius
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstraße 40 48149 Münster Deutschland
| |
Collapse
|
39
|
Patra A, Mukherjee S, Das TK, Jain S, Gonnade RG, Biju AT. N-Heterocyclic-Carbene-Catalyzed Umpolung of Imines. Angew Chem Int Ed Engl 2017; 56:2730-2734. [DOI: 10.1002/anie.201611268] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/04/2017] [Indexed: 12/22/2022]
Affiliation(s)
- Atanu Patra
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
- Academy of Scientific and Innovative Research (AcSIR); New Delhi 110020 India
| | - Subrata Mukherjee
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
- Academy of Scientific and Innovative Research (AcSIR); New Delhi 110020 India
| | - Tamal Kanti Das
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
- Academy of Scientific and Innovative Research (AcSIR); New Delhi 110020 India
| | - Shailja Jain
- Physical/Materials Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
| | - Rajesh G. Gonnade
- Centre for Materials Characterization; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
| | - Akkattu T. Biju
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
- Academy of Scientific and Innovative Research (AcSIR); New Delhi 110020 India
| |
Collapse
|
40
|
Janssen-Müller D, Singha S, Lied F, Gottschalk K, Glorius F. NHC-Organocatalyzed CAr
−O Bond Cleavage: Mild Access to 2-Hydroxybenzophenones. Angew Chem Int Ed Engl 2017; 56:6276-6279. [DOI: 10.1002/anie.201610203] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 01/03/2017] [Indexed: 12/24/2022]
Affiliation(s)
- Daniel Janssen-Müller
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstrasse 40 48149 Münster Germany
| | - Santanu Singha
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstrasse 40 48149 Münster Germany
| | - Fabian Lied
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstrasse 40 48149 Münster Germany
| | - Karin Gottschalk
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstrasse 40 48149 Münster Germany
| | - Frank Glorius
- Westfälische Wilhelms-Universität Münster; Organisch-Chemisches Institut; Corrensstrasse 40 48149 Münster Germany
| |
Collapse
|
41
|
Patra A, Mukherjee S, Das TK, Jain S, Gonnade RG, Biju AT. N-Heterocyclic-Carbene-Catalyzed Umpolung of Imines. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201611268] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Atanu Patra
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
- Academy of Scientific and Innovative Research (AcSIR); New Delhi 110020 India
| | - Subrata Mukherjee
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
- Academy of Scientific and Innovative Research (AcSIR); New Delhi 110020 India
| | - Tamal Kanti Das
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
- Academy of Scientific and Innovative Research (AcSIR); New Delhi 110020 India
| | - Shailja Jain
- Physical/Materials Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
| | - Rajesh G. Gonnade
- Centre for Materials Characterization; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
| | - Akkattu T. Biju
- Organic Chemistry Division; CSIR-National Chemical Laboratory; Dr. Homi Bhabha Road Pune- 411008 India
- Academy of Scientific and Innovative Research (AcSIR); New Delhi 110020 India
| |
Collapse
|
42
|
Zhang G, Xu W, Liu J, Das DK, Yang S, Perveen S, Zhang H, Li X, Fang X. Enantioselective intermolecular all-carbon [4+2] annulation via N-heterocyclic carbene organocatalysis. Chem Commun (Camb) 2017; 53:13336-13339. [DOI: 10.1039/c7cc08680f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The challenge of asymmetric intermolecular all-carbon [4+2] annulation via α,β-unsaturated acyl azoliums was addressed with 2-acyloxy-3-butenones as suitable dienolate precursors, and a variety of highly functionalized cyclohexene products were delivered at a high level of enantioselectivity.
Collapse
Affiliation(s)
- Guoxiang Zhang
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| | - Weici Xu
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| | - Jian Liu
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| | - Deb Kumar Das
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| | - Shuang Yang
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| | - Saima Perveen
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| | - Hao Zhang
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| | - Xinglong Li
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| | - Xinqiang Fang
- State Key Laboratory of Structural Chemistry, and Key Laboratory of Coal to Ethylene Glycol and Its Related Technology
- Fujian Institute of Research on the Structure of Matter (FJIRSM)
- University of Chinese Academy of Sciences
- Fuzhou 350100
- China
| |
Collapse
|
43
|
Mukherjee S, Joseph S, Bhunia A, Gonnade RG, Yetra SR, Biju AT. Enantioselective synthesis of spiro γ-butyrolactones by N-heterocyclic carbene (NHC)-catalyzed formal [3 + 2] annulation of enals with 3-hydroxy oxindoles. Org Biomol Chem 2017; 15:2013-2019. [DOI: 10.1039/c7ob00148g] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The NHC-catalyzed enantioselective, oxidative formal [3 + 2] annulation of α,β-unsaturated aldehydes with 3-hydroxy oxindoles is presented.
Collapse
Affiliation(s)
- Subrata Mukherjee
- Organic Chemistry Division
- CSIR-National Chemical Laboratory (CSIR-NCL)
- Pune-411008
- India
| | - Sumi Joseph
- Organic Chemistry Division
- CSIR-National Chemical Laboratory (CSIR-NCL)
- Pune-411008
- India
| | - Anup Bhunia
- Organic Chemistry Division
- CSIR-National Chemical Laboratory (CSIR-NCL)
- Pune-411008
- India
| | - Rajesh G. Gonnade
- Centre for Materials Characterization
- CSIR-National Chemical Laboratory (CSIR-NCL)
- Pune-411008
- India
| | | | - Akkattu T. Biju
- Organic Chemistry Division
- CSIR-National Chemical Laboratory (CSIR-NCL)
- Pune-411008
- India
| |
Collapse
|
44
|
Affiliation(s)
- Neanne Alnafta
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Johannes P. Schmidt
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Caroline L. Nesbitt
- School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | | |
Collapse
|
45
|
Levens A, Ametovski A, Lupton DW. Enantioselective (4+2) Annulation of Donor-Acceptor Cyclobutanes by N-Heterocyclic Carbene Catalysis. Angew Chem Int Ed Engl 2016; 55:16136-16140. [PMID: 27891746 DOI: 10.1002/anie.201609330] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Revised: 10/31/2016] [Indexed: 12/22/2022]
Abstract
Herein we report the enantioselective (4+2) annulation of donor-acceptor cyclobutanes and unsaturated acyl fluorides using N-heterocyclic carbene catalysis. The reaction allows a 3-step synthesis of cyclohexyl β-lactones (25 examples) in excellent chemical yield (most ≥90 %) and stereochemical integrity (all >20:1 d.r., most ≥97:3 e.r.). Mechanistic studies support ester enolate Claisen rearrangement, while derivatizations provide functionalized cyclohexenes and dihydroquinolinones.
Collapse
Affiliation(s)
- Alison Levens
- School of Chemistry, Monash University, Clayton, 3800, Victoria, Australia
| | - Adam Ametovski
- School of Chemistry, Monash University, Clayton, 3800, Victoria, Australia
| | - David W Lupton
- School of Chemistry, Monash University, Clayton, 3800, Victoria, Australia
| |
Collapse
|
46
|
Levens A, Ametovski A, Lupton DW. Enantioselective (4+2) Annulation of Donor-Acceptor Cyclobutanes by N-Heterocyclic Carbene Catalysis. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201609330] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Alison Levens
- School of Chemistry; Monash University; Clayton 3800 Victoria Australia
| | - Adam Ametovski
- School of Chemistry; Monash University; Clayton 3800 Victoria Australia
| | - David W. Lupton
- School of Chemistry; Monash University; Clayton 3800 Victoria Australia
| |
Collapse
|
47
|
Ema T, Nanjo Y, Shiratori S, Terao Y, Kimura R. Solvent-Free Benzoin and Stetter Reactions with a Small Amount of NHC Catalyst in the Liquid or Semisolid State. Org Lett 2016; 18:5764-5767. [DOI: 10.1021/acs.orglett.6b03115] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Tadashi Ema
- Division
of Applied Chemistry,
Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan
| | - Yoshiko Nanjo
- Division
of Applied Chemistry,
Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan
| | - Sho Shiratori
- Division
of Applied Chemistry,
Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan
| | - Yuta Terao
- Division
of Applied Chemistry,
Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan
| | - Ryo Kimura
- Division
of Applied Chemistry,
Graduate School of Natural Science and Technology, Okayama University, Tsushima, Okayama 700-8530, Japan
| |
Collapse
|
48
|
Janssen-Müller D, Singha S, Olyschläger T, Daniliuc CG, Glorius F. Annulation of o-Quinodimethanes through N-Heterocyclic Carbene Catalysis for the Synthesis of 1-Isochromanones. Org Lett 2016; 18:4444-7. [DOI: 10.1021/acs.orglett.6b02335] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Daniel Janssen-Müller
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße
40, 48149 Münster, Germany
| | - Santanu Singha
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße
40, 48149 Münster, Germany
| | - Theresa Olyschläger
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße
40, 48149 Münster, Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße
40, 48149 Münster, Germany
| | - Frank Glorius
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße
40, 48149 Münster, Germany
| |
Collapse
|
49
|
Janssen-Müller D, Fleige M, Schlüns D, Wollenburg M, Daniliuc CG, Neugebauer J, Glorius F. NHC-Catalyzed Enantioselective Dearomatizing Hydroacylation of Benzofurans and Benzothiophenes for the Synthesis of Spirocycles. ACS Catal 2016. [DOI: 10.1021/acscatal.6b01852] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel Janssen-Müller
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe
40, 48149 Münster, Germany
| | - Mirco Fleige
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe
40, 48149 Münster, Germany
| | - Danny Schlüns
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe
40, 48149 Münster, Germany
- Center
for Multiscale Theory and Computation, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149 Münster, Germany
| | - Marco Wollenburg
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe
40, 48149 Münster, Germany
| | - Constantin G. Daniliuc
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe
40, 48149 Münster, Germany
| | - Johannes Neugebauer
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe
40, 48149 Münster, Germany
- Center
for Multiscale Theory and Computation, Westfälische Wilhelms-Universität Münster, Corrensstraβe 40, 48149 Münster, Germany
| | - Frank Glorius
- Organisch-Chemisches
Institut, Westfälische Wilhelms-Universität Münster, Corrensstraβe
40, 48149 Münster, Germany
| |
Collapse
|
50
|
Levens A, An F, Breugst M, Mayr H, Lupton DW. Influence of the N-Substituents on the Nucleophilicity and Lewis Basicity of N-Heterocyclic Carbenes. Org Lett 2016; 18:3566-9. [PMID: 27434216 DOI: 10.1021/acs.orglett.6b01525] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ability to modulate the nucleophilicity and Lewis basicity of N-heterocyclic carbenes is pivotal to their application as organocatalysts. Herein we examine the impact of the N-substituent on the nucleophilicity and Lewis basicity. Four N-substituents popular in NHC organocatalysis, namely, the N-2,6-(CH3O)2C6H3, N-Mes, N-4-CH3OC6H4, and N-tert-butyl groups, have been examined and found to strongly affect the nucleophilicity. Thus, the N-2,6-(CH3O)2C6H3 group provides the most nucleophilic imidazolylidene NHC reported and the N-tert-butyl group one of the least. This difference in nucleophilicity is reflected in the catalyst efficiency, as observed with a recently reported trienyl ester rearrangement.
Collapse
Affiliation(s)
- Alison Levens
- School of Chemistry, Monash University , Clayton, Victoria 3800, Australia
| | - Feng An
- Department Chemie, Ludwig-Maximilians-Universität München , Butenandtstraße 5-13 (Haus F), 81377 München, Germany
| | - Martin Breugst
- Department für Chemie, Universität zu Köln , Greinstraße 4, 50939 Köln, Germany
| | - Herbert Mayr
- Department Chemie, Ludwig-Maximilians-Universität München , Butenandtstraße 5-13 (Haus F), 81377 München, Germany
| | - David W Lupton
- School of Chemistry, Monash University , Clayton, Victoria 3800, Australia
| |
Collapse
|