1
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Chauhan S, Swamy KCK. Phosphine vs DBU-Catalyzed Annulation Reactions of β'-Acetoxy Allenoates with Acyl-Tethered Benzothiazole Bisnucleophiles: (4 + 3) or (4 + 1) vs (3 + 3) Annulation. J Org Chem 2024; 89:10816-10830. [PMID: 39007762 DOI: 10.1021/acs.joc.4c01085] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/16/2024]
Abstract
Dearomative annulation reaction of acyl-tethered benzothiazole bisnucleophiles with β'-acetoxy allenoates by switching the Lewis base is developed. The DBU-catalyzed reaction gives benzothiazole-fused 1,4-dihydropyridine carboxylates by (3 + 3) annulation chemoselectively. By contrast, the PR3-catalyzed reaction gives benzothiazole-fused azepines by (4 + 3) annulation and cyclopentene carboxylates by (4 + 1) annulation; the ratio of the latter two products depends on the solvent. A possible rationale for the difference in the reactivity, based on the 1,4/1,5-addition of the 2-acyl-tethered benzothiazole to the key phosphonium intermediate, is provided.
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Affiliation(s)
- Sachin Chauhan
- School of Chemistry, University of Hyderabad, Hyderabad 500046, Telangana, India
| | - K C Kumara Swamy
- School of Chemistry, University of Hyderabad, Hyderabad 500046, Telangana, India
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2
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Song X, Qin W, Wang X, Luo G, Ni Q. Bifunctional Squaramide-Catalyzed Asymmetric Cascade Reaction of Benzothiazoles with 2-Nitroallylic Acetates or Nitroenynes. Org Lett 2023; 25:9164-9169. [PMID: 38097282 DOI: 10.1021/acs.orglett.3c03692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2023]
Abstract
We describe here an organocatalytic asymmetric cascade formal [3 + 3] cycloaddition of benzothiazoles with 2-nitroallylic acetates and nitroenynes. This dearomative methodology provided a facile and efficient strategy for the construction of a broad range of valuable benzothiazolopyridines bearing two adjacent stereogenic centers in moderate to good yields with good to excellent stereocontrol.
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Affiliation(s)
- Xiaoxiao Song
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials (State Key Laboratory Cultivation Base), College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241002, P. R. China
| | - Wei Qin
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials (State Key Laboratory Cultivation Base), College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241002, P. R. China
| | - Xuyang Wang
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials (State Key Laboratory Cultivation Base), College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241002, P. R. China
| | - Gen Luo
- Institutes of Physical Science and Information Technology, Anhui University, Hefei 230601, China
| | - Qijian Ni
- Key Laboratory of Functionalized Molecular Solids, Ministry of Education, Anhui Key Laboratory of Molecule-Based Materials (State Key Laboratory Cultivation Base), College of Chemistry and Materials Science, Anhui Normal University, Wuhu, Anhui 241002, P. R. China
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3
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Liu L, Wen C, Sun G, Li Y, Zhang J, Zhang Z, Wang Z, She M, Liu P, Zhang S, Li J. Multisite-Sequential Cyclization To Construct 1,2,4-Triazole-Based N-Fused Heterocyclics. Org Lett 2023; 25:1530-1535. [PMID: 36852941 DOI: 10.1021/acs.orglett.3c00322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
A feasible protocol that uses atomic groups (KSCN, KSeCN, and NH2CN), o-bromobenzoyl hydrazides, and formyls as reaction factors to synthesize N-fused 1,2,4-triazole with benzothiazides, benzoselenazinones, and quinazolinones was proposed. The method overcomes the lengthy multistep synthesis, narrow substrate scope, and toxicity challenge induced by the use or production of hazardous substances. It also enables the development of fused-heterocyclic selenium and quinazolinone derivatives. Their fluorescent performance further demonstrates the practicability of this methodology.
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Affiliation(s)
- Lang Liu
- College of Chemistry & Materials Science, Northwest University, Xi'an 710069, China
| | - Changting Wen
- College of Chemistry & Materials Science, Northwest University, Xi'an 710069, China
| | - Guojin Sun
- College of Chemistry & Materials Science, Northwest University, Xi'an 710069, China
| | - Yao Li
- College of Chemistry & Materials Science, Northwest University, Xi'an 710069, China
| | - Jun Zhang
- College of Chemistry and Chemical Engineering, Ningxia University Yinchuan, Ningxia, 750021, P. R. China
| | - Zhe Zhang
- College of Chemistry & Materials Science, Northwest University, Xi'an 710069, China
| | - Zesi Wang
- College of Chemistry & Materials Science, Northwest University, Xi'an 710069, China
| | - Mengyao She
- Ministry of Education Key Laboratory of Resource Biology and Modern Biotechnology in Western China, The College of Life Sciences, Faculty of Life and Health Science, Northwest University, Xi'an, Shaanxi Province 710069, P. R. China
| | - Ping Liu
- College of Chemistry & Materials Science, Northwest University, Xi'an 710069, China
| | - Shengyong Zhang
- College of Chemistry & Materials Science, Northwest University, Xi'an 710069, China
| | - Jianli Li
- Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, Xi'an Key Laboratory of Functional Supramolecular Structure and Materials, College of Chemistry & Materials Science, Northwest University, Xi'an, Shaanxi 710127, P. R. China
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4
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Ag 2O/squaramide cocatalyzed asymmetric interrupted Barton-Zard reaction of 8-nitroimidazo[1,2-a]pyridines. Sci Bull (Beijing) 2022; 67:1688-1695. [PMID: 36546048 DOI: 10.1016/j.scib.2022.07.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Revised: 07/02/2022] [Accepted: 07/13/2022] [Indexed: 01/07/2023]
Abstract
Imidazo[1,2-a]pyridines are present in numerous biologically active compounds as the core structural motif. Herein, we report an asymmetric interrupted Barton-Zard reaction of electron-deficient imidazo[1,2-a]pyridines with α-substituted isocyanoacetates. The reaction enables the dearomatization of 8-nitroimidazo[1,2-a]pyridines and hence offers straightforward access to an array of optically active highly functionalized imidazo[1,2-a]pyridine derivatives that possess three contiguous stereogenic centers in good yields (up to 98%) with high stereoselectivities (>19:1 dr, >99% ee). It is worth noting that the catalytic system consisting of a chiral squaramide and silver oxide displays remarkable reactivity and stereoselectivity, and a gram-scale reaction is compatible with the catalyst loading of 0.5 mol%. In addition, the synthetic potential of this method was showcased by versatile transformations of the product.
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5
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Bitai J, Nimmo AJ, Slawin AMZ, Smith AD. Cooperative Palladium/Isothiourea Catalyzed Enantioselective Formal (3+2) Cycloaddition of Vinylcyclopropanes and α,β-Unsaturated Esters. Angew Chem Int Ed Engl 2022; 61:e202202621. [PMID: 35389553 PMCID: PMC9324207 DOI: 10.1002/anie.202202621] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Indexed: 12/15/2022]
Abstract
A protocol for the enantioselective synthesis of substituted vinylcyclopentanes has been realised using cooperative palladium and isothiourea catalysis. Treatment of vinylcyclopropanes with Pd(PPh3 )4 generates a zwitterionic π-allyl palladium intermediate that intercepts a catalytically generated α,β-unsaturated acyl ammonium species prepared from the corresponding α,β-unsaturated para-nitrophenyl ester and the isothiourea (R)-BTM. Intermolecular formal (3+2) cycloaddition between these reactive intermediates generates functionalised cyclopentanes in generally good yields and excellent diastereo- and enantiocontrol (up to >95 : 5 dr, 97 : 3 er), with the use of LiCl as an additive proving essential for optimal stereocontrol. To the best of our knowledge a dual transition metal/organocatalytic process involving α,β-unsaturated acyl ammonium intermediates has not been demonstrated previously.
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Affiliation(s)
- Jacqueline Bitai
- EaStCHEM, School of ChemistryUniversity of St AndrewsSt Andrews, FifeKY16 9STUK
| | - Alastair J. Nimmo
- EaStCHEM, School of ChemistryUniversity of St AndrewsSt Andrews, FifeKY16 9STUK
| | | | - Andrew D. Smith
- EaStCHEM, School of ChemistryUniversity of St AndrewsSt Andrews, FifeKY16 9STUK
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6
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Bitai J, Nimmo AJ, Slawin AMZ, Smith AD. Cooperative Palladium/Isothiourea Catalyzed Enantioselective Formal (3+2) Cycloaddition of Vinylcyclopropanes and a,b‐Unsaturated Esters. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202202621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
| | | | | | - Andrew David Smith
- University of St Andrews School of Chemistry North Haugh FIFE, KY10 3TH St. Andrews UNITED KINGDOM
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7
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Maitland JAP, Leitch JA, Yamazaki K, Christensen KE, Cassar DJ, Hamlin TA, Dixon DJ. Switchable, Reagent‐Controlled Diastereodivergent Photocatalytic Carbocyclisation of Imine‐Derived α‐Amino Radicals. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202107253] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- J. Andrew P. Maitland
- Department of Chemistry Chemistry Research Laboratory University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | - Jamie A. Leitch
- Department of Chemistry Chemistry Research Laboratory University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
- Current address: Department of Pharmaceutical and Biological Chemistry UCL (University College London) School of Pharmacy 29–39 Brunswick Square London WC1N 1AX UK
| | - Ken Yamazaki
- Department of Chemistry Chemistry Research Laboratory University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
- Department of Theoretical Chemistry Amsterdam Institute of Molecular and Life Sciences (AIMMS) Amsterdam Center for Multiscale Modeling (ACMM) Vrije Universiteit Amsterdam De Boelelaan 1083 1081 HV Amsterdam The Netherlands
| | - Kirsten E. Christensen
- Department of Chemistry Chemistry Research Laboratory University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
| | | | - Trevor A. Hamlin
- Department of Theoretical Chemistry Amsterdam Institute of Molecular and Life Sciences (AIMMS) Amsterdam Center for Multiscale Modeling (ACMM) Vrije Universiteit Amsterdam De Boelelaan 1083 1081 HV Amsterdam The Netherlands
| | - Darren J. Dixon
- Department of Chemistry Chemistry Research Laboratory University of Oxford 12 Mansfield Road Oxford OX1 3TA UK
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8
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Maitland JAP, Leitch JA, Yamazaki K, Christensen KE, Cassar DJ, Hamlin TA, Dixon DJ. Switchable, Reagent-Controlled Diastereodivergent Photocatalytic Carbocyclisation of Imine-Derived α-Amino Radicals. Angew Chem Int Ed Engl 2021; 60:24116-24123. [PMID: 34449968 PMCID: PMC8597041 DOI: 10.1002/anie.202107253] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 08/13/2021] [Indexed: 12/15/2022]
Abstract
A reagent-controlled stereodivergent carbocyclisation of aryl aldimine-derived, photocatalytically generated, α-amino radicals possessing adjacent conjugated alkenes, affording either bicyclic or tetracyclic products, is described. Under net reductive conditions using commercial Hantzsch ester, the α-amino radical species underwent a single stereoselective cyclisation to give trans-configured amino-indane structures in good yield, whereas using a substituted Hantzsch ester as a milder reductant afforded cis-fused tetracyclic tetrahydroquinoline frameworks, resulting from two consecutive radical cyclisations. Judicious choice of the reaction conditions allowed libraries of both single and dual cyclisation products to be synthesised with high selectivity, notable predictability, and good-to-excellent yields. Computational analysis employing DFT revealed the reaction pathway and mechanistic rationale behind this finely balanced yet readily controlled photocatalytic system.
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Affiliation(s)
- J. Andrew P. Maitland
- Department of ChemistryChemistry Research LaboratoryUniversity of Oxford12 Mansfield RoadOxfordOX1 3TAUK
| | - Jamie A. Leitch
- Department of ChemistryChemistry Research LaboratoryUniversity of Oxford12 Mansfield RoadOxfordOX1 3TAUK
- Current address: Department of Pharmaceutical and Biological ChemistryUCL (University College London)School of Pharmacy29–39 Brunswick SquareLondonWC1N 1AXUK
| | - Ken Yamazaki
- Department of ChemistryChemistry Research LaboratoryUniversity of Oxford12 Mansfield RoadOxfordOX1 3TAUK
- Department of Theoretical ChemistryAmsterdam Institute of Molecular and Life Sciences (AIMMS)Amsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
| | - Kirsten E. Christensen
- Department of ChemistryChemistry Research LaboratoryUniversity of Oxford12 Mansfield RoadOxfordOX1 3TAUK
| | | | - Trevor A. Hamlin
- Department of Theoretical ChemistryAmsterdam Institute of Molecular and Life Sciences (AIMMS)Amsterdam Center for Multiscale Modeling (ACMM)Vrije Universiteit AmsterdamDe Boelelaan 10831081 HVAmsterdamThe Netherlands
| | - Darren J. Dixon
- Department of ChemistryChemistry Research LaboratoryUniversity of Oxford12 Mansfield RoadOxfordOX1 3TAUK
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9
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Bitai J, Westwood MT, Smith AD. α,β-Unsaturated acyl ammonium species as reactive intermediates in organocatalysis: an update. Org Biomol Chem 2021; 19:2366-2384. [PMID: 33650626 DOI: 10.1039/d0ob02208j] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
α,β-Unsaturated acyl ammonium species are versatile intermediates that have been applied in a variety of transformations including Michael additions, domino reactions and cycloadditions. Many of these transformations are promoted by chiral Lewis base catalysts, enabling the rapid generation of molecular complexity with high stereochemical control. This review highlights recent developments in the generation and application of α,β-unsaturated acyl ammonium intermediates reported since a previous review of this area in 2016. Particular emphasis will be placed on reports providing mechanistic insight into catalytic transformations and observed selectivities. A perspective on current challenges and potential future developments in the field of α,β-unsaturated acyl ammonium catalysis is also provided.
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Affiliation(s)
- Jacqueline Bitai
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, Fife, Scotland, KY16 9ST, UK.
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10
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Ahlemeyer NA, Straub MR, Leace DM, Matz BA, Birman VB. Cascade Cyclizations of α,β-Unsaturated Thioesters: Additional Examples. J Org Chem 2021; 86:1191-1197. [PMID: 33307686 DOI: 10.1021/acs.joc.0c02091] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Several additional examples of cascade cyclizations of α,β-unsaturated thioesters proceeding are reported, which proceed via two distinct mechanistic pathways: enantioselective acyl transfer promoted by amidine-based catalysts (ABCs) and a racemic chain mechanism mediated by a thiolate nucleophile.
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Affiliation(s)
- Nicholas A Ahlemeyer
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, St. Louis, Missouri 63130, United States
| | - Matthew R Straub
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, St. Louis, Missouri 63130, United States
| | - David M Leace
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, St. Louis, Missouri 63130, United States
| | - Benjamin A Matz
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, St. Louis, Missouri 63130, United States
| | - Vladimir B Birman
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, St. Louis, Missouri 63130, United States
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11
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Biswas A, Mondal H, Maji MS. Synthesis of Heterocycles by isothiourea organocatalysis. J Heterocycl Chem 2020. [DOI: 10.1002/jhet.4119] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Anup Biswas
- Department of Chemistry Hooghly Women's College Hooghly India
| | - Haripriyo Mondal
- Department of Chemistry Indian Institute of Technology Kharagpur India
| | - Modhu S. Maji
- Department of Chemistry Indian Institute of Technology Kharagpur India
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12
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Zhang YC, Geng RL, Song J, Gong LZ. Isothiourea and Brønsted Acid Cooperative Catalysis: Enantioselective Construction of Dihydropyridinones. Org Lett 2020; 22:2261-2265. [DOI: 10.1021/acs.orglett.0c00461] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Yu-Chen Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Rui-Long Geng
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Jin Song
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Liu-Zhu Gong
- Hefei National Laboratory for Physical Sciences at the Microscale and Department of Chemistry, University of Science and Technology of China, Hefei 230026, China
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13
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Liu H, Slawin AMZ, Smith AD. Isothiourea-Catalyzed Enantioselective Synthesis of Tetrahydro-α-carbolinones. Org Lett 2020; 22:1301-1305. [DOI: 10.1021/acs.orglett.9b04615] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Honglei Liu
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, U.K
| | - Alexandra M. Z. Slawin
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, U.K
| | - Andrew D. Smith
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife KY16 9ST, U.K
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14
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Shu C, Liu H, Slawin AMZ, Carpenter-Warren C, Smith AD. Isothiourea-catalysed enantioselective Michael addition of N-heterocyclic pronucleophiles to α,β-unsaturated aryl esters. Chem Sci 2019; 11:241-247. [PMID: 34040717 PMCID: PMC8133005 DOI: 10.1039/c9sc04303a] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The isothiourea-catalysed enantioselective Michael addition of 3-aryloxindole and 4-substituted-dihydropyrazol-3-one pronucleophiles to α,β-unsaturated p-nitrophenyl esters is reported. This process generates products containing two contiguous stereocentres, one quaternary, in good yields and excellent enantioselectivities (>30 examples, up to > 95 : 5 dr and 99 : 1 er). This protocol harnesses the multifunctional ability of p-nitrophenoxide to promote effective catalysis. In contrast to previous methodologies using tertiary amine Lewis bases, in which the pronucleophile was used as the solvent, this work allows bespoke pronucleophiles to be used in stoichiometric quantities. The isothiourea-catalysed enantioselective Michael addition of 3-aryloxindole and 4-substituted-dihydropyrazol-3-one pronucleophiles to α,β-unsaturated p-nitrophenyl esters is reported.![]()
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Affiliation(s)
- Chang Shu
- EaStCHEM, School of Chemistry, University of St Andrews North Haugh, St Andrews Fife KY16 9ST UK
| | - Honglei Liu
- EaStCHEM, School of Chemistry, University of St Andrews North Haugh, St Andrews Fife KY16 9ST UK
| | - Alexandra M Z Slawin
- EaStCHEM, School of Chemistry, University of St Andrews North Haugh, St Andrews Fife KY16 9ST UK
| | - Cameron Carpenter-Warren
- EaStCHEM, School of Chemistry, University of St Andrews North Haugh, St Andrews Fife KY16 9ST UK
| | - Andrew D Smith
- EaStCHEM, School of Chemistry, University of St Andrews North Haugh, St Andrews Fife KY16 9ST UK
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15
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McLaughlin C, Slawin AMZ, Smith AD. Base‐free Enantioselective C(1)‐Ammonium Enolate Catalysis Exploiting Aryloxides: A Synthetic and Mechanistic Study. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201908627] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- Calum McLaughlin
- EaStCHEM School of Chemistry University of St Andrews North Haugh Fife Scotland KY16 9ST UK
| | - Alexandra M. Z. Slawin
- EaStCHEM School of Chemistry University of St Andrews North Haugh Fife Scotland KY16 9ST UK
| | - Andrew D. Smith
- EaStCHEM School of Chemistry University of St Andrews North Haugh Fife Scotland KY16 9ST UK
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16
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McLaughlin C, Slawin AMZ, Smith AD. Base-free Enantioselective C(1)-Ammonium Enolate Catalysis Exploiting Aryloxides: A Synthetic and Mechanistic Study. Angew Chem Int Ed Engl 2019; 58:15111-15119. [PMID: 31436380 DOI: 10.1002/anie.201908627] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Indexed: 12/21/2022]
Abstract
An isothiourea-catalyzed enantioselective Michael addition of aryl ester pronucleophiles to vinyl bis-sulfones via C(1)-ammonium enolate intermediates has been developed. This operationally simple method allows the base-free functionalization of aryl esters to form α-functionalized products containing two contiguous tertiary stereogenic centres in excellent yield and stereoselectivity (all ≥99:1 er). Key to the success of this methodology is the multifunctional role of the aryloxide, which operates as a leaving group, Brønsted base, Brønsted acid and Lewis base within the catalytic cycle. Comprehensive mechanistic studies, including variable time normalization analysis (VTNA) and isotopologue competition experiments, have been carried out. These studies have identified (i) orders of all reactants; (ii) a turnover-limiting Michael addition step, (iii) product inhibition, (iv) the catalyst resting state and (v) catalyst deactivation through protonation.
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Affiliation(s)
- Calum McLaughlin
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, Fife, Scotland, KY16 9ST, UK
| | - Alexandra M Z Slawin
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, Fife, Scotland, KY16 9ST, UK
| | - Andrew D Smith
- EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, Fife, Scotland, KY16 9ST, UK
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17
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Leace DM, Straub MR, Matz BA, Birman VB. Organocatalyzed Rearrangement of S-(2-Oxoalkyl)-thioenoates. J Org Chem 2019; 84:7523-7531. [DOI: 10.1021/acs.joc.9b00925] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- David M. Leace
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, Saint Louis, Missouri 63130, United States
| | - Matthew R. Straub
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, Saint Louis, Missouri 63130, United States
| | - Benjamin A. Matz
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, Saint Louis, Missouri 63130, United States
| | - Vladimir B. Birman
- Department of Chemistry, Washington University, Campus Box 1134, One Brookings Drive, Saint Louis, Missouri 63130, United States
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18
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Abstract
Detailed NMR spectral analysis of DMSO-d6 solutions of the series of substituted 2-phenacylbenzimidazoles (ketimine form, K) reveals two from three tautomeric forms. Integrals of the 1H NMR signals are used in establishing the molar ratio of tautomers. The experimental analyses are supported by quantum-chemical calculations, which satisfactorily reproduced the experimental trends. Although the reported semiempirical quantum-chemical calculations show that enaminone E, i.e., 2-(1,3-dihydro-2H-benzo[d]imidazol-2-ylidene)-1-phenylethan-1-one, was thermodynamically most stable, the results of MP2 ab initio calculations reveal the following order of stability: ketimine > enolimine > enaminone (substituents do not affect this sequence). 13C CPMAS NMR spectral data reveal that in the crystalline state the enolimine tautomer O is predominant in the p-CH3 and p-NO2 substituted congeners.
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19
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Young CM, Taylor JE, Smith AD. Evaluating aryl esters as bench-stable C(1)-ammonium enolate precursors in catalytic, enantioselective Michael addition–lactonisations. Org Biomol Chem 2019; 17:4747-4752. [DOI: 10.1039/c9ob00703b] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
An evaluation of a range of aryl, alkyl and vinyl esters as prospective C(1)-ammonium enolate precursors in enantioselective Michael addition–lactonisation processes with (E)-trifluoromethylenones using isothiourea catalysis is reported.
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Affiliation(s)
- Claire M. Young
- EaStCHEM
- School of Chemistry
- University of St Andrews
- North Haugh
- UK
| | - James E. Taylor
- EaStCHEM
- School of Chemistry
- University of St Andrews
- North Haugh
- UK
| | - Andrew D. Smith
- EaStCHEM
- School of Chemistry
- University of St Andrews
- North Haugh
- UK
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20
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Enantioselective synthesis of indolo[2,3-b]-dihydrothiopyranones via [3+3] cycloaddition of chiral α,β-unsaturated acylammonium salts. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.09.024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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21
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Zhang CL, Zhang ZF, Xia ZH, Han YF, Ye S. DBU-Mediated Construction of 1,3,5-Trisubstituted Benzenes via Annulation of α,β-Unsaturated Carboxylic Acids and α-Cyano-β-methylenones. J Org Chem 2018; 83:12507-12513. [PMID: 30247035 DOI: 10.1021/acs.joc.8b01740] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A DBU-mediated synthesis of 1,3,5-trisubstituted benzenes was developed via the [2 + 4] annulation of in situ activated α,β-unsaturated carboxylic acids and α-cyano-β-methylenones. The dual role of DBU as Brønsted base and nucleophilic Lewis base is the key for the success of the reaction.
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Affiliation(s)
- Chun-Lin Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China
| | - Zhao-Fei Zhang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Zi-Hao Xia
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
| | - You-Feng Han
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Song Ye
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry , Chinese Academy of Sciences , Beijing 100190 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
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22
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Greenhalgh MD, Qu S, Slawin AMZ, Smith AD. Multiple roles of aryloxide leaving groups in enantioselective annulations employing α,β-unsaturated acyl ammonium catalysis. Chem Sci 2018; 9:4909-4918. [PMID: 29910944 PMCID: PMC5982221 DOI: 10.1039/c8sc01324a] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 05/04/2018] [Indexed: 12/13/2022] Open
Abstract
An isothiourea-catalysed Michael addition-annulation process using β-fluoroalkyl-substituted α,β-unsaturated aryl esters and a range of 2-acylbenzazoles is reported for the enantioselective synthesis of dihydropyranone and dihydropyridinone products bearing polyfluorinated stereocenters (29 examples, up to 98% yield, >99 : 1 er). The choice of aryl group of the aryl ester proved essential in determining reaction enantioselectivity and dihydropyranone : dihydropyridinone product selectivity. The aryloxide leaving group is shown to play a number of essential additional roles, operating (i) as a Brønsted base, circumventing the need for an auxiliary base; and (ii) as a Lewis base to catalyse the isomerisation of dihydropyranone products into thermodynamically-favoured dihydropyridinones. After optimisation, this isomerisation process was exploited for the selective synthesis of dihydropyridinone products using acylbenzothiazoles, and either dihydropyranone or dihydropyridinone products using acylbenzoxazoles. Finally, the phenol derivative, produced following protonation of the aryloxide, is proposed to act as a Brønsted acid, which promotes an isothiourea-catalysed kinetic resolution of benzoxazole-derived dihydropyranones.
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Affiliation(s)
- Mark D Greenhalgh
- EaStCHEM , School of Chemistry , University of St Andrews , North Haugh , St Andrews KY16 9ST , UK .
| | - Shen Qu
- EaStCHEM , School of Chemistry , University of St Andrews , North Haugh , St Andrews KY16 9ST , UK .
| | - Alexandra M Z Slawin
- EaStCHEM , School of Chemistry , University of St Andrews , North Haugh , St Andrews KY16 9ST , UK .
| | - Andrew D Smith
- EaStCHEM , School of Chemistry , University of St Andrews , North Haugh , St Andrews KY16 9ST , UK .
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23
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Kang G, Yamagami M, Vellalath S, Romo D. Enantioselective Synthesis of Medium‐Sized Lactams via Chiral α,β‐Unsaturated Acylammonium Salts. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201802483] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Guowei Kang
- Department of Chemistry and Biochemistry Baylor University One Bear Place #97348 Waco TX 76798-7348 USA
| | - Masaki Yamagami
- Biomolecular Chemistry Laboratory Department of Chemistry Graduate School of Science 1-1 Machikaneyama, Toyonaka Osaka 560-0043 Japan
| | - Sreekumar Vellalath
- Department of Chemistry and Biochemistry Baylor University One Bear Place #97348 Waco TX 76798-7348 USA
| | - Daniel Romo
- Department of Chemistry and Biochemistry Baylor University One Bear Place #97348 Waco TX 76798-7348 USA
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24
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Kang G, Yamagami M, Vellalath S, Romo D. Enantioselective Synthesis of Medium-Sized Lactams via Chiral α,β-Unsaturated Acylammonium Salts. Angew Chem Int Ed Engl 2018; 57:6527-6531. [PMID: 29624841 DOI: 10.1002/anie.201802483] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Indexed: 11/12/2022]
Abstract
Medium-sized lactams are important structural motifs found in a variety of bioactive compounds and natural products but are challenging to prepare, especially in optically active form. A Michael addition/proton transfer/lactamization organocascade process is described that delivers medium-sized lactams, including azepanones, benzazepinones, azocanones, and benzazocinones, in high enantiopurity through the intermediacy of chiral α,β-unsaturated acylammonium salts. An unexpected indoline synthesis was also uncovered, and the benzazocinone skeleton was transformed into other complex heterocyclic derivatives, including spiroglutarimides, isoquinolinones, and δ-lactones.
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Affiliation(s)
- Guowei Kang
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX, 76798-7348, USA
| | - Masaki Yamagami
- Biomolecular Chemistry Laboratory, Department of Chemistry, Graduate School of Science, 1-1 Machikaneyama, Toyonaka, Osaka, 560-0043, Japan
| | - Sreekumar Vellalath
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX, 76798-7348, USA
| | - Daniel Romo
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, TX, 76798-7348, USA
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25
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Abbasov ME, Hudson BM, Kong W, Tantillo DJ, Romo D. Enantioselective Diels-Alder-lactamization organocascades employing a furan-based diene. Org Biomol Chem 2018; 15:3179-3183. [PMID: 28358148 DOI: 10.1039/c6ob02738e] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
α,β-Unsaturated acylammonium salts are useful dienophiles enabling highly enantioselective and stereodivergent Diels-Alder-initiated organocascades with furan-based dienes. Complex polycyclic systems can thus be obtained from readily prepared dienes, commodity acid chlorides, and a chiral isothiourea organocatalyst under mild conditions. We describe the use of furan-based dienes bearing pendant sulfonamides leading to the generation of oxa-bridged, trans-fused tricyclic γ-lactams. This process constitutes the first highly enantio- and diastereoselective, organocatalytic Diels-Alder cycloadditions with these typically problematic dienes due to their reversibility. Computational studies suggest that the high diastereoselectivity with these furan dienes may be due to a reversible Diels-Alder cycloaddition for the endo adducts. In addition, the utility of this methodology is demonstrated through a concise approach to a core structure with similarity to the natural product isatisine A and a nonpeptidyl ghrelin-receptor inverse agonist.
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Affiliation(s)
- Mikail E Abbasov
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, Texas 76798, USA.
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26
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Hu Y, Pan D, Cong L, Yao Y, Yu C, Li T, Yao C. NHC-Catalyzed Efficient Syntheses of Isoquinolinones or Isochromanones through Formal [4+2] Cycloaddition of o
-Quinodimethanes with Acylhydrazones or Ketones. ChemistrySelect 2018. [DOI: 10.1002/slct.201702925] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Yong Hu
- Jiangsu Key Lab of Green Synthetic Chemistry for Functional Materials; School of Chemistry and Materials Science; Jiangsu Normal university, Xuzhou; Jiangsu 221116, P.R. China
| | - Di Pan
- Jiangsu Key Lab of Green Synthetic Chemistry for Functional Materials; School of Chemistry and Materials Science; Jiangsu Normal university, Xuzhou; Jiangsu 221116, P.R. China
| | - Lin Cong
- Jiangsu Key Lab of Green Synthetic Chemistry for Functional Materials; School of Chemistry and Materials Science; Jiangsu Normal university, Xuzhou; Jiangsu 221116, P.R. China
| | - Yibiao Yao
- Jiangsu Key Lab of Green Synthetic Chemistry for Functional Materials; School of Chemistry and Materials Science; Jiangsu Normal university, Xuzhou; Jiangsu 221116, P.R. China
| | - Chenxia Yu
- Jiangsu Key Lab of Green Synthetic Chemistry for Functional Materials; School of Chemistry and Materials Science; Jiangsu Normal university, Xuzhou; Jiangsu 221116, P.R. China
| | - Tuanjie Li
- Jiangsu Key Lab of Green Synthetic Chemistry for Functional Materials; School of Chemistry and Materials Science; Jiangsu Normal university, Xuzhou; Jiangsu 221116, P.R. China
| | - Changsheng Yao
- Jiangsu Key Lab of Green Synthetic Chemistry for Functional Materials; School of Chemistry and Materials Science; Jiangsu Normal university, Xuzhou; Jiangsu 221116, P.R. China
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27
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Van KN, Romo D. Multicomponent, Enantioselective Michael-Michael-Aldol-β-Lactonizations Delivering Complex β-Lactones. J Org Chem 2018; 83:632-643. [PMID: 29219311 DOI: 10.1021/acs.joc.7b02543] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Optically active, tertiary amine Lewis bases react with unsaturated acid chlorides to deliver chiral, α,β-unsaturated acylammonium salts. These intermediates participate in a catalytic, enantioselective, three-component process delivering bi- and tricyclic β-lactones through a Michael-Michael-aldol-β-lactonization. In a single operation, the described multicomponent, organocascade process forms complex bi- and tricyclic β-lactones by generating four new bonds, two rings, and up to four contiguous stereocenters. In the racemic series, yields of 22-75% were achieved using 4-pyrrolidinopyridine as Lewis base. In the enantioselective series employing isothiourea catalysts, a kinetic resolution of the initially formed racemic Michael adduct appears operative, providing yields of 46% to quantitative (based on 50% max) with up to 94:6 er. Some evidence for a dynamic kinetic asymmetric transformation for tricyclic-β-lactone 1d was obtained following optimization (yields up to 61%, 94:6 er) through a presumed reversible Michael.
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Affiliation(s)
- Khoi N Van
- Department of Chemistry, Texas A&M University , College Station, Texas 77842, United States
| | - Daniel Romo
- Department of Chemistry & Biochemistry, Baylor University , Waco, Texas 76798, United States
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28
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Matviitsuk A, Greenhalgh MD, Antúnez DB, Slawin AMZ, Smith AD. Aryloxide-Facilitated Catalyst Turnover in Enantioselective α,β-Unsaturated Acyl Ammonium Catalysis. Angew Chem Int Ed Engl 2017; 56:12282-12287. [PMID: 28791763 PMCID: PMC5638104 DOI: 10.1002/anie.201706402] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Indexed: 11/27/2022]
Abstract
A new general concept for α,β-unsaturated acyl ammonium catalysis is reported that uses p-nitrophenoxide release from an α,β-unsaturated p-nitrophenyl ester substrate to facilitate catalyst turnover. This method was used for the enantioselective isothiourea-catalyzed Michael addition of nitroalkanes to α,β-unsaturated p-nitrophenyl esters in generally good yield and with excellent enantioselectivity (27 examples, up to 79 % yield, 99:1 er). Mechanistic studies identified rapid and reversible catalyst acylation by the α,β-unsaturated p-nitrophenyl ester, and a recently reported variable-time normalization kinetic analysis method was used to delineate the complex reaction kinetics.
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Affiliation(s)
- Anastassia Matviitsuk
- EaStCHEMSchool of ChemistryUniversity of St AndrewsNorth HaughSt AndrewsFifeKY16 9STUK
| | - Mark D. Greenhalgh
- EaStCHEMSchool of ChemistryUniversity of St AndrewsNorth HaughSt AndrewsFifeKY16 9STUK
| | | | | | - Andrew D. Smith
- EaStCHEMSchool of ChemistryUniversity of St AndrewsNorth HaughSt AndrewsFifeKY16 9STUK
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29
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Matviitsuk A, Greenhalgh MD, Antúnez DJB, Slawin AMZ, Smith AD. Aryloxide-Facilitated Catalyst Turnover in Enantioselective α,β-Unsaturated Acyl Ammonium Catalysis. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201706402] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Anastassia Matviitsuk
- EaStCHEM; School of Chemistry; University of St Andrews; North Haugh St Andrews Fife KY16 9ST UK
| | - Mark D. Greenhalgh
- EaStCHEM; School of Chemistry; University of St Andrews; North Haugh St Andrews Fife KY16 9ST UK
| | | | - Alexandra M. Z. Slawin
- EaStCHEM; School of Chemistry; University of St Andrews; North Haugh St Andrews Fife KY16 9ST UK
| | - Andrew D. Smith
- EaStCHEM; School of Chemistry; University of St Andrews; North Haugh St Andrews Fife KY16 9ST UK
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30
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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.
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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
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31
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Liu Q, Wang J, Li D, Gao GL, Yang C, Gao Y, Xia W. Synthesis of Oxatricyclooctanes via Photoinduced Intramolecular Oxa-[4+2] Cycloaddition of Substituted o-Divinylbenzenes. J Org Chem 2017; 82:7856-7868. [PMID: 28699349 DOI: 10.1021/acs.joc.7b01055] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The photolysis of substituted o-divinylbenzenes promotes a one-step and metal-free conversion to oxatricycles at room temperature. Irradiation o-divinylbenzenes results in an pericyclic reaction to form cyclic o-quinodiemthane intermediates, which subsequently undergo intramolecular oxa-[4+2] cycloaddition to form oxacyclic derivatives.
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Affiliation(s)
- Qiang Liu
- State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology (Shenzhen) , Shenzhen 518055, China
| | - Junlei Wang
- State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology (Shenzhen) , Shenzhen 518055, China
| | - Dazhi Li
- State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology (Shenzhen) , Shenzhen 518055, China
| | - Guo-Lin Gao
- State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology (Shenzhen) , Shenzhen 518055, China
| | - Chao Yang
- State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology (Shenzhen) , Shenzhen 518055, China
| | - Yuan Gao
- School of Chemistry and chemical Engineering, Yantai University , #30 Qingquan RD, Laishan District, Yantai 264005, China
| | - Wujiong Xia
- State Key Lab of Urban Water Resource and Environment, Harbin Institute of Technology (Shenzhen) , Shenzhen 518055, China
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32
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Matviitsuk A, Taylor JE, Cordes DB, Slawin AMZ, Smith AD. Enantioselective Stereodivergent Nucleophile-Dependent Isothiourea-Catalysed Domino Reactions. Chemistry 2016; 22:17748-17757. [PMID: 27727506 PMCID: PMC5132085 DOI: 10.1002/chem.201603318] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Indexed: 11/12/2022]
Abstract
α,β-Unsaturated acyl ammoniums generated from the reaction of α,β-unsaturated 2,4,6-trichlorophenol (TCP) esters bearing a pendent enone with an isothiourea organocatalyst are versatile intermediates in a range of enantioselective nucleophile-dependent domino processes to form complex products of diverse topology with excellent stereoselectivity. Use of either 1,3-dicarbonyls, acyl benzothiazoles, or acyl benzimidazoles as nucleophiles allows three distinct, diastereodivergent domino reaction pathways to be accessed to form various fused polycyclic cores containing multiple contiguous stereocentres.
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Affiliation(s)
- Anastassia Matviitsuk
- EaStCHEMSchool of ChemistryUniversity of St. Andrews, North HaughSt. AndrewsFifeKY16 9STUK
| | - James E. Taylor
- EaStCHEMSchool of ChemistryUniversity of St. Andrews, North HaughSt. AndrewsFifeKY16 9STUK
| | - David B. Cordes
- EaStCHEMSchool of ChemistryUniversity of St. Andrews, North HaughSt. AndrewsFifeKY16 9STUK
| | - Alexandra M. Z. Slawin
- EaStCHEMSchool of ChemistryUniversity of St. Andrews, North HaughSt. AndrewsFifeKY16 9STUK
| | - Andrew D. Smith
- EaStCHEMSchool of ChemistryUniversity of St. Andrews, North HaughSt. AndrewsFifeKY16 9STUK
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