151
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Breman AC, Telderman SEM, van Santen RPM, Scott JI, van Maarseveen JH, Ingemann S, Hiemstra H. Cinchona Alkaloid Catalyzed Sulfa-Michael Addition Reactions Leading to Enantiopure β-Functionalized Cysteines. J Org Chem 2015; 80:10561-74. [DOI: 10.1021/acs.joc.5b01660] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Arjen C. Breman
- Van’t Hoff Institute
for Molecular Sciences, Faculty of Science, The University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Suze E. M. Telderman
- Van’t Hoff Institute
for Molecular Sciences, Faculty of Science, The University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Roy P. M. van Santen
- Van’t Hoff Institute
for Molecular Sciences, Faculty of Science, The University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Jamie I. Scott
- Van’t Hoff Institute
for Molecular Sciences, Faculty of Science, The University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Jan H. van Maarseveen
- Van’t Hoff Institute
for Molecular Sciences, Faculty of Science, The University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Steen Ingemann
- Van’t Hoff Institute
for Molecular Sciences, Faculty of Science, The University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Henk Hiemstra
- Van’t Hoff Institute
for Molecular Sciences, Faculty of Science, The University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
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152
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Zhang ZP, Dong N, Li X, Cheng JP. Highly enantioselective Michael addition reactions of 2-substituted benzofuran-3(2H)-ones to nitroolefins. Org Biomol Chem 2015; 13:9943-7. [PMID: 26349788 DOI: 10.1039/c5ob01691f] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A highly enantioselective Michael addition reaction of 2-substituted benzofuran-3(2H)-ones to nitroolefins was promoted by a bifunctional squaramide catalyst. As a result, a number of chiral 2,2'-substituted benzofuran-3-one derivatives, bearing adjacent quaternary-tertiary stereocenters, were efficiently synthesized with excellent enantioselectivities.
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Affiliation(s)
- Zhi-Pei Zhang
- State Key Laboratory of Elemento-Organic Chemistry, Department of Chemistry, Nankai University, Tianjin 300071, China.
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153
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Mortezaei S, Catarineu NR, Duan X, Hu C, Canary JW. Redox-configurable ambidextrous catalysis: structural and mechanistic insight. Chem Sci 2015; 6:5904-5912. [PMID: 29861915 PMCID: PMC5950827 DOI: 10.1039/c5sc02144h] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Accepted: 07/13/2015] [Indexed: 01/19/2023] Open
Abstract
A helically chiral copper complex is used as a switchable asymmetric catalyst capable of delivering either enantiomer of a Michael addition reaction.
A ligand capable of adopting two pseudo-enantiomeric helically chiral states when bound to copper has been applied as an asymmetric catalyst in the Michael addition of malonate substrates to nitrostyrenes. The absolute configuration of the helically chiral ligand is inverted upon oxidation/reduction of the copper center. In this way, the handedness of the Michael addition product (R/S) can be selected based on the handedness of the catalyst (Λ/Δ). Exciton coupled circular dichroism (ECCD) was used to identify which of the two pseudo-enantiomeric forms the catalyst adopted after reduction/oxidation, with additional support from X-ray crystallographic data. The synthesis of the ligand was achieved in five steps with an overall 61% yield. Enantiomeric excesses of the Michael addition products of up to 72% (S) and 70% (R) were obtained in acetonitrile. The ability to choose the handedness of the product based on the chiral state of the catalyst has been demonstrated with several different solvents, bases, nitrostyrene/malonate substrates, and prochiral malonate substrates. A combination of molecular modelling, crystal structure and kinetic data suggest that one urea moiety of the catalyst ligand likely binds the nitrostyrene substrate while blocking the Re face of the nitrostyrene in the transition state.
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Affiliation(s)
- Shahab Mortezaei
- Department of Chemistry , New York University , New York , New York 10003 , USA .
| | - Noelle R Catarineu
- Department of Chemistry , New York University , New York , New York 10003 , USA .
| | - Xueyou Duan
- Department of Chemistry , New York University , New York , New York 10003 , USA .
| | - Chunhua Hu
- Department of Chemistry , New York University , New York , New York 10003 , USA .
| | - James W Canary
- Department of Chemistry , New York University , New York , New York 10003 , USA .
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154
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Asymmetric synthesis of syn-propargylamines and unsaturated β-amino acids under Brønsted base catalysis. Nat Commun 2015; 6:8544. [PMID: 26423837 PMCID: PMC4600747 DOI: 10.1038/ncomms9544] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 09/01/2015] [Indexed: 12/05/2022] Open
Abstract
Propargylamines are important intermediates for the synthesis of polyfunctional amino derivatives and natural products and biologically active compounds. The classic method of synthesizing chiral propargylamines involves the asymmetric alkynylation of imines. Here, we report a significant advance in the catalytic asymmetric Mannich-type synthesis of propargylamines through catalytic asymmetric addition of carbon nucleophiles to C-alkynyl imines, culminating in a highly syn-selective catalytic asymmetric Mannich reaction of C-alkynyl imines that provide syn-configured propargylamines with two adjacent stereogenic centres and a transition metal-free organocatalytic asymmetric approach to β-alkynyl-β-amino acids with high efficiency and practicality, via a chiral Brønsted base-catalysed asymmetric Mannich-type reaction of in situ generated challenging N-Boc C-alkynyl imines from previously unreported C-alkynyl N-Boc-N,O-acetals, with α-substituted β-keto esters and less-acidic malonate (thio)esters as nucleophiles, respectively. A catalytic activation strategy is also disclosed, which may have broad implications for use in catalysis and synthesis. Propargylamines are of interest both as biologically active compounds and versatile synthetic intermediates. Here, the authors report a method for the organocatalytic asymmetric synthesis of propargylamines through addition of carbon nucleophiles to alkynyl imines.
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155
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Raveendra B, Maity S, Das BG, Ghorai P. Organocatalytic, Enantioselective Synthesis of 1- and 3-Substituted Isochromans via Intramolecular Oxa-Michael Reaction of Alkoxyboronate: Synthesis of (+)-Sonepiprazole. J Org Chem 2015; 80:7008-18. [PMID: 26102523 DOI: 10.1021/acs.joc.5b00719] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The enantioselective oxa-Michael reaction of alkoxyboronate strategy was demonstrated to provide a new and practical route to enantioriched 1- and 3-substituted isochromans using a chiral bifunctional organocatalyst. Furthermore, this methodology was extended to the enantioselective synthesis of (+)-sonepiprazole, a dopamine receptor antagonist.
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Affiliation(s)
- Barnala Raveendra
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Indore By-pass Road, Bhauri, Bhopal-462066, India
| | - Sanjay Maity
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Indore By-pass Road, Bhauri, Bhopal-462066, India
| | - Braja Gopal Das
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Indore By-pass Road, Bhauri, Bhopal-462066, India
| | - Prasanta Ghorai
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Indore By-pass Road, Bhauri, Bhopal-462066, India
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156
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Zhang H, Wang B, Cui L, Li Y, Qu J, Song Y. Organocatalytic enantioselective α-amination of 5-substituted rhodanines: an efficient approach to chiral N,S-acetals. Org Biomol Chem 2015; 12:9097-100. [PMID: 25298316 DOI: 10.1039/c4ob01921k] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
We report a highly efficient approach to constructing chiral N,S-acetals using 5-substituted rhodanines as sulfur-bound pronucleophiles catalyzed by natural cinchona alkaloids quinine or quinidine. This α-amination reaction has a broad substrate scope, and the products featuring both rhodanine and N,S-acetal structural motifs were obtained in high yields and excellent enantioselectivities.
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Affiliation(s)
- Huanrui Zhang
- State Key Laboratory of Fine Chemicals, School of Pharmaceutical Science and Technology, Dalian University of Technology, Dalian 116024, P. R. China.
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157
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García Mancheño O, Asmus S, Zurro M, Fischer T. Hoch enantioselektive nukleophile Dearomatisierung von Pyridinen durch Anionenbindungskatalyse. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201502708] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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158
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García Mancheño O, Asmus S, Zurro M, Fischer T. Highly Enantioselective Nucleophilic Dearomatization of Pyridines by Anion-Binding Catalysis. Angew Chem Int Ed Engl 2015; 54:8823-7. [PMID: 26111052 DOI: 10.1002/anie.201502708] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 05/01/2015] [Indexed: 01/20/2023]
Abstract
The asymmetric dearomatization of N-heterocycles is an important synthetic method to gain bioactive and synthetically valuable chiral heterocycles. However, the catalytic enantio- and regioselective dearomatization of the simplest six-membered-ring N-heteroarenes, the pyridines, is still very challenging. The first anion-binding-catalyzed, highly enantioselective nucleophilic dearomatization of pyridines with triazole-based H-bond donor catalysts is presented. Contrary to other more common NH-based H-bond donors, this type of organocatalyst shows a prominent higher C2-regioselectivity and is able to promote high enantioinductions via formation of a close chiral anion-pair complex with a preformed N-acyl pyridinium ionic intermediate. This method offers a straightforward and useful synthetic approach to chiral N-heterocycles from abundant and readily available pyridines.
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Affiliation(s)
- Olga García Mancheño
- Institute for Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg (Germany). .,Straubing Center of Science for Renewable Resources (WZS), Schulgasse 16, Straubing (Germany).
| | - Sören Asmus
- Institute for Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg (Germany)
| | - Mercedes Zurro
- Institute for Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg (Germany)
| | - Theresa Fischer
- Institute for Organic Chemistry, University of Regensburg, Universitätsstrasse 31, 93053 Regensburg (Germany)
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159
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Sekikawa T, Kitaguchi T, Kitaura H, Minami T, Hatanaka Y. Catalytic Activity of epi-Quinine-Derived 3,5-Bis(trifluoromethyl)benzamide in Asymmetric Nitro-Michael Reaction of Furanones. Org Lett 2015; 17:3026-9. [DOI: 10.1021/acs.orglett.5b01224] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Affiliation(s)
- Tohru Sekikawa
- Department
of Applied Chemistry,
Graduate School of Engineering, Osaka City University, Sumiyoshi, Osaka 558-8585, Japan
| | - Takayuki Kitaguchi
- Department
of Applied Chemistry,
Graduate School of Engineering, Osaka City University, Sumiyoshi, Osaka 558-8585, Japan
| | - Hayato Kitaura
- Department
of Applied Chemistry,
Graduate School of Engineering, Osaka City University, Sumiyoshi, Osaka 558-8585, Japan
| | - Tatsuya Minami
- Department
of Applied Chemistry,
Graduate School of Engineering, Osaka City University, Sumiyoshi, Osaka 558-8585, Japan
| | - Yasuo Hatanaka
- Department
of Applied Chemistry,
Graduate School of Engineering, Osaka City University, Sumiyoshi, Osaka 558-8585, Japan
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160
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Engl OD, Fritz SP, Wennemers H. Stereoselective Organocatalytic Synthesis of Oxindoles with Adjacent Tetrasubstituted Stereocenters. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201502976] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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161
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Asymmetric addition of 3-substituted benzofuran-2-ones to isatin N-Boc ketimines catalyzed by chiral biscinchona alkaloid catalyst. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.04.114] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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162
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Engl OD, Fritz SP, Wennemers H. Stereoselective Organocatalytic Synthesis of Oxindoles with Adjacent Tetrasubstituted Stereocenters. Angew Chem Int Ed Engl 2015; 54:8193-7. [DOI: 10.1002/anie.201502976] [Citation(s) in RCA: 74] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2015] [Revised: 05/05/2015] [Indexed: 01/07/2023]
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163
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Bae HY, Song CE. Unprecedented Hydrophobic Amplification in Noncovalent Organocatalysis “on Water”: Hydrophobic Chiral Squaramide Catalyzed Michael Addition of Malonates to Nitroalkenes. ACS Catal 2015. [DOI: 10.1021/acscatal.5b00685] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Han Yong Bae
- Department
of Chemistry, Sungkyunkwan University, Gyeonggi, 440-746, Korea
| | - Choong Eui Song
- Department
of Chemistry, Sungkyunkwan University, Gyeonggi, 440-746, Korea
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164
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Lu H, Bai J, Xu J, Yang T, Lin X, Li J, Ren F. Chiral 2-aminopyrimidin-4(1H)-one derivative as the novel bifunctional organocatalyst: enantioselective Aldol reaction of isatins with ketones. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.03.053] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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165
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Wang R, Jing L, Qin D. Organocatalytic asymmetric Michael addition of benzofuran-2(3H)-ones to alkylideneindolenines generated in situ from arenesulfonylalkylindoles. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.04.071] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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166
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Liu T, Liu W, Li X, Peng F, Shao Z. Catalytic Asymmetric Construction of Vicinal Tetrasubstituted Stereocenters by the Mannich Reaction of Linear α-Substituted Monothiomalonates with Isatin N-Boc Ketimines. J Org Chem 2015; 80:4950-6. [PMID: 25897636 DOI: 10.1021/acs.joc.5b00302] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
A highly diastereo- and enantioselective method for the construction of vicinal tetrasubstituted stereocenters through the first catalytic asymmetric Mannich reaction of linear α-substituted MTMs with isatin N-Boc ketimines has been developed. This protocol provides atom-economic synthesis of less accessible 3-aminooxindoles bearing vicinal tetrasubstituted stereocenters. Notably, it also constitutes the first example of stereoselective synthesis of β-amino thioesters bearing vicinal tetrasubstituted stereocenters.
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Affiliation(s)
- Teng Liu
- †Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Weiwei Liu
- †Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Xiaonian Li
- ‡Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China
| | - Fangzhi Peng
- †Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
| | - Zhihui Shao
- †Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming 650091, China
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167
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Zhang H, Wang B, Cui L, Bao X, Qu J, Song Y. Organocatalytic Asymmetric Fluorination of 4-Substituted Isoxazolinones. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500046] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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168
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Wu B, Gao X, Chen MW, Zhou YG. Direct amination of 2-(1-tosylalkyl)phenols with aqueous ammonia: a metal-free synthesis of primary amines. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2015.01.078] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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169
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Molleti N, Singh VK. Highly enantioselective synthesis of naphthoquinones and pyranonaphthoquinones catalyzed by bifunctional chiral bis-squaramides. Org Biomol Chem 2015; 13:5243-54. [DOI: 10.1039/c5ob00105f] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A variety of enantioenriched naphthoquinones has been synthesized in high yields and excellent enantioselectivities (up to >99% ee) using a bifunctional chiral bis-squaramide catalyzed conjugate addition of 2-hydroxy-1,4-naphthoquinone to 2-enoylpyridines.
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Affiliation(s)
- Nagaraju Molleti
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal-462 066
- India
| | - Vinod K. Singh
- Department of Chemistry
- Indian Institute of Science Education and Research Bhopal
- Bhopal-462 066
- India
- Department of Chemistry
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170
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Kumar TP, Radhika L, Haribabu K, Kumar VN. Pyrrolidine-oxyimides: new chiral catalysts for enantioselective Michael addition of ketones to nitroolefins in water. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.tetasy.2014.10.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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171
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Mukherjee T, Ganzmann C, Bhuvanesh N, Gladysz JA. Syntheses of Enantiopure Bifunctional 2-Guanidinobenzimidazole Cyclopentadienyl Ruthenium Complexes: Highly Enantioselective Organometallic Hydrogen Bond Donor Catalysts for Carbon–Carbon Bond Forming Reactions. Organometallics 2014. [DOI: 10.1021/om500705s] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Tathagata Mukherjee
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - Carola Ganzmann
- Institut für Organische Chemie and Interdisciplinary Center
for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 42, 91054 Erlangen, Germany
| | - Nattamai Bhuvanesh
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
| | - John A. Gladysz
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, United States
- Institut für Organische Chemie and Interdisciplinary Center
for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestraße 42, 91054 Erlangen, Germany
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172
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Kwiatkowski P, Cholewiak A, Kasztelan A. Efficient and Highly Enantioselective Construction of Trifluoromethylated Quaternary Stereogenic Centers via High-Pressure Mediated Organocatalytic Conjugate Addition of Nitromethane to β,β-Disubstituted Enones. Org Lett 2014; 16:5930-3. [DOI: 10.1021/ol502941d] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Piotr Kwiatkowski
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
| | - Agnieszka Cholewiak
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
| | - Adrian Kasztelan
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland
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173
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Raveendra B, Das BG, Ghorai P. Organocatalytic, enantioselective, intramolecular oxa-Michael reaction of alkoxyboronate: a new strategy for enantioenriched 1-substituted 1,3-dihydroisobenzofurans. Org Lett 2014; 16:5580-3. [PMID: 25337660 DOI: 10.1021/ol502614n] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
An unprecedented strategy for the synthesis of enantioenriched 1-substituted 1,3-dihydroisobenzofurans via an enantioselective oxa-Michael reaction of o-alkoxyboronate containing chalcone (II) has been accomplished employing cinchona alkaloid based squaramide bifunctional organocatalyst in the presence of proton source. The corresponding alkoxyboronate intermediates have been readily prepared in situ from o-formyl chalcones using neutral borane as hydride source and a tertiary amine moiety which is a counterpart of the catalyst.
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Affiliation(s)
- Barnala Raveendra
- Department of Chemistry, Indian Institute of Science Education and Research Bhopal , Bhauri, Bhopal 462066, India
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174
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Chen YM, Amireddy M, Chen K. Organocatalytic desymmetrization of cyclic meso-anhydrides through enantioselective alcoholysis with functionalized primary nitroallylic alcohols. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.10.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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175
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Kataja AO, Masson G. Imine and iminium precursors as versatile intermediates in enantioselective organocatalysis. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.06.101] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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176
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Yin XP, Zeng XP, Liu YL, Liao FM, Yu JS, Zhou F, Zhou J. Asymmetric Triple Relay Catalysis: Enantioselective Synthesis of Spirocyclic Indolines through a One-Pot Process Featuring an Asymmetric 6π Electrocyclization. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201407677] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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177
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Yin XP, Zeng XP, Liu YL, Liao FM, Yu JS, Zhou F, Zhou J. Asymmetric Triple Relay Catalysis: Enantioselective Synthesis of Spirocyclic Indolines through a One-Pot Process Featuring an Asymmetric 6π Electrocyclization. Angew Chem Int Ed Engl 2014; 53:13740-5. [DOI: 10.1002/anie.201407677] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Revised: 09/02/2014] [Indexed: 12/15/2022]
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178
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Engl OD, Fritz SP, Käslin A, Wennemers H. Organocatalytic Route to Dihydrocoumarins and Dihydroquinolinones in All Stereochemical Configurations. Org Lett 2014; 16:5454-7. [DOI: 10.1021/ol502697s] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Oliver D. Engl
- ETH Zürich, Laboratory for Organic Chemistry, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Sven P. Fritz
- ETH Zürich, Laboratory for Organic Chemistry, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Alexander Käslin
- ETH Zürich, Laboratory for Organic Chemistry, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Helma Wennemers
- ETH Zürich, Laboratory for Organic Chemistry, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
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179
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Ričko S, Golobič A, Svete J, Stanovnik B, Grošelj U. Synthesis of novel camphor-derived bifunctional thiourea organocatalysts. Chirality 2014; 27:39-52. [PMID: 25283890 DOI: 10.1002/chir.22386] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 08/13/2014] [Indexed: 11/06/2022]
Abstract
Synthesis and catalyst performance of 2,3- (types and ) and 2,8-disubstituted (type ) thiourea bifunctional organocatalysts was attempted. The synthesis of catalyst of type has, so far, not been realized, while catalysts of type , i.e., the 2,3-exo- and the 2-endo-3-exo-thiourea catalysts, were prepared in six steps starting from (+)-camphor. The catalysts of type were prepared from (+)-camphor in eight steps. All the potential catalysts as well as most of the intermediate products were carefully structurally characterized. The thiourea bifunctional organocatalysts were tested in a model reaction of Michael addition of dimethyl malonate to trans-β-nitrostyrene.
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Affiliation(s)
- Sebastijan Ričko
- University of Ljubljana, Faculty of Chemistry and Chemical Technology, Ljubljana, Slovenia
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180
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Lefranc A, Gremaud L, Alexakis A. Construction of Bicyclo[3.2.1]octanes with Four Stereogenic Centers by Organocatalytic Domino Michael/Aldol Reaction. Org Lett 2014; 16:5242-5. [DOI: 10.1021/ol502171h] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- A. Lefranc
- Department
of Organic Chemistry, University of Geneva, quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
| | - L. Gremaud
- Department
of Organic Chemistry, University of Geneva, quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
| | - A. Alexakis
- Department
of Organic Chemistry, University of Geneva, quai Ernest Ansermet 30, CH-1211 Geneva 4, Switzerland
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181
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Kumar TP. Asymmetric Michael addition of aldehydes to nitroolefins catalyzed by a pyrrolidine–pyrazole. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.tetasy.2014.07.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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182
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Kayal S, Mukherjee S. Catalytic Asymmetric Michael Addition/Cyclization Cascade Reaction of 3-Isothiocyanatooxindoles with Nitro Olefins. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402534] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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183
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Phelan JP, Patel EJ, Ellman JA. Catalytic Enantioselective Addition of Thioacids to Trisubstituted Nitroalkenes. Angew Chem Int Ed Engl 2014; 53:11329-32. [DOI: 10.1002/anie.201406971] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Indexed: 11/07/2022]
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184
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Phelan JP, Patel EJ, Ellman JA. Catalytic Enantioselective Addition of Thioacids to Trisubstituted Nitroalkenes. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201406971] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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185
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Palmer JH, Parkin G. Synthesis and Structural Characterization of 1-Arylimidazole-2-thiones and N, N'-Aryldiethoxyethylthioureas with Electronically Diverse Substituents: A Manifold of Hydrogen Bonding Networks. NEW J CHEM 2014; 38:4071-4082. [PMID: 25214759 PMCID: PMC4157683 DOI: 10.1039/c4nj00521j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The 1-arylimidazole-2-thiones, (HmimAr) [Ar = 3,4,5-C6H2(OMe)3, 2,4-C6H3(NO2)(OMe), 2,4,6-C6H2Cl3 and 3,5-C6H3(CF3)2], which feature electronically diverse substituents, may be obtained via acid-catalyzed ring closure of the corresponding N,N'-aryldiethoxyethylthiourea derivatives, ArN(H)C(S)N(H)CH2CH(OEt)2, (H2detuAr), which in turn are obtained via treatment of aminoacetaldehyde diethyl acetal, H2NCH2CH(OEt)2, with the respective arylisothiocyanates (ArNCS). The molecular structures of all of the above N,N'-aryldiethoxyethylthioureas and 1-arylimidazole-2-thiones have been determined by X-ray diffraction, thereby demonstrating that the substituents have a profound effect on the crystal structures. For example, each of the N,N'-aryldiethoxyethylthiourea derivatives adopts a different hydrogen bonding pattern. Specifically, the hydrogen-bonding network in (i) H2detuArCl3 consists of chains of 9-membered rings, with an [ [Formula: see text](9)] motif, that feature one N-H ⋯ O and one N-H ⋯ S interaction, (ii) H2detuArOMe,NO2 consists of chains of 6-membered rings, with an [ [Formula: see text](6)] motif, that feature two head-to-tail N-H ⋯ S interactions, (iii) H2detuAr(CF3)2 consists of a dimer that features two pairs of N-H ⋯ O interactions, of which each pair is a component of an 8-membered ring with an [ [Formula: see text](8)] motif, and (iv) H2detuAr(OMe)3 consists of a chain of head-to-head dimeric rings with a basic [ [Formula: see text](16)] motif, a notable feature of which is that sulfur does not play a role as a hydrogen bond acceptor. Each of the 1-arylimidazole-2-thiones exists as a "head-to-head" hydrogen-bonded dimer in the solid state, with an [ [Formula: see text](8)] motif. However, while the hydrogen-bonded motifs for HmimArCl3 and HmimAr(OMe)3 are planar, those for HmimAr(CF3)2 and HmimArOMe,NO2 are extremely puckered, with fold angles of 24.2° (mean value) and 45.7°, respectively.
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Affiliation(s)
- Joshua H. Palmer
- Department of Chemistry, Columbia University, New York, New York 10027,
USA
| | - Gerard Parkin
- Department of Chemistry, Columbia University, New York, New York 10027,
USA
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186
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Song Y, Cheng C, Jing H. Aza-Crown Ether Complex Cation Ionic Liquids: Preparation and Applications in Organic Reactions. Chemistry 2014; 20:12894-900. [DOI: 10.1002/chem.201403118] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Indexed: 11/10/2022]
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187
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Kolarovic A, Käslin A, Wennemers H. Stereoselective Synthesis of Indolines via Organocatalytic Thioester Enolate Addition Reactions. Org Lett 2014; 16:4236-9. [DOI: 10.1021/ol501936n] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Andrej Kolarovic
- ETH Zürich, Laboratorium für Organische Chemie, Vladimir-Prelog-Weg 3, CH-8093 Zürich, Switzerland
| | - Alexander Käslin
- ETH Zürich, Laboratorium für Organische Chemie, Vladimir-Prelog-Weg 3, CH-8093 Zürich, Switzerland
| | - Helma Wennemers
- ETH Zürich, Laboratorium für Organische Chemie, Vladimir-Prelog-Weg 3, CH-8093 Zürich, Switzerland
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188
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Liu YL, Liao FM, Niu YF, Zhao XL, Zhou J. Highly stereoselective construction of adjacent tetrasubstituted carbon stereogenic centres via an organocatalytic Mukaiyama-aldol reaction of monofluorinated silyl enol ethers to isatins. Org Chem Front 2014. [DOI: 10.1039/c4qo00126e] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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189
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Corbett M, Xu Q, Johnson JS. Trisubstituted 2-trifluoromethyl pyrrolidines via catalytic asymmetric Michael addition/reductive cyclization. Org Lett 2014; 16:2362-5. [PMID: 24746344 PMCID: PMC4011570 DOI: 10.1021/ol500679w] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2014] [Indexed: 01/16/2023]
Abstract
The stereoselective synthesis of trisubstituted 2-trifluoromethyl pyrrolidines by asymmetric Michael addition/hydrogenative cyclization is described. The direct organocatalytic addition of 1,1,1-trifluoromethylketones to nitroolefins proceeds under mild reaction conditions and low catalyst loadings to provide Michael adducts in high yield with excellent diastereo- and enantioselectivity. Catalytic hydrogenation of the Michael adducts stereoselectively generates 2-trifluoromethylated pyrrolidines bearing three contiguous stereocenters. A stereospecific route to epimeric 2-trifluoromethyl pyrrolidines from a common intermediate is described.
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Affiliation(s)
- Michael
T. Corbett
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Qihai Xu
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
| | - Jeffrey S. Johnson
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States
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190
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Arakawa Y, Fritz SP, Wennemers H. Organocatalytic Stereoselective Synthesis of Acyclic γ-Nitrothioesters with All-Carbon Quaternary Stereogenic Centers. J Org Chem 2014; 79:3937-45. [DOI: 10.1021/jo500403q] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Yukihiro Arakawa
- Laboratory
of Organic Chemistry,
D-CHAB, ETH Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Sven P. Fritz
- Laboratory
of Organic Chemistry,
D-CHAB, ETH Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
| | - Helma Wennemers
- Laboratory
of Organic Chemistry,
D-CHAB, ETH Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich, Switzerland
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191
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Diosdado S, López R, Palomo C. Ureidopeptide‐Based Brønsted Bases: Design, Synthesis and Application to the Catalytic Enantioselective Synthesis of β‐Amino Nitriles from (Arylsulfonyl)acetonitriles. Chemistry 2014; 20:6526-31. [DOI: 10.1002/chem.201304877] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 02/19/2014] [Indexed: 12/11/2022]
Affiliation(s)
- Saioa Diosdado
- Departamento de Química Orgánica I, Facultad de Química, Universidad del País Vasco, Apdo. 1072, 20080 San Sebastián (Spain)
| | - Rosa López
- Departamento de Química Orgánica I, Facultad de Química, Universidad del País Vasco, Apdo. 1072, 20080 San Sebastián (Spain)
| | - Claudio Palomo
- Departamento de Química Orgánica I, Facultad de Química, Universidad del País Vasco, Apdo. 1072, 20080 San Sebastián (Spain)
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192
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Sun Z, Zhou M, Li X, Meng X, Peng F, Zhang H, Shao Z. Catalytic asymmetric assembly of octahydroindolones: divergent synthesis of lycorine-type amaryllidaceae alkaloids (+)-α-lycorane and (+)-lycorine. Chemistry 2014; 20:6112-9. [PMID: 24700723 DOI: 10.1002/chem.201400178] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2014] [Indexed: 11/07/2022]
Abstract
We report the first catalytic asymmetric approach to octahydroindolones and a divergent enantioselective synthesis of perhydroindole alkaloids, as exemplified by lycorine-type Amaryllidaceae alkaloids (+)-α-lycorane and (+)-lycorine, from a common intermediate by using a highly concise route. The assembly of octahydroindolones employs a catalytic enantioselective 1,4-conjugate addition of nitro dienynes, followed by a TsOH-catalyzed cascade synthesis of highly functionalized enones, and a diastereoselective intramolecular Michael addition.
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Affiliation(s)
- Zhongwen Sun
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan 650091 (P.R. China), Fax: (+86) 871-65035538
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193
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Zhu XL, Xu JH, Cheng DJ, Zhao LJ, Liu XY, Tan B. In Situ Generation of Electrophilic Trifluoromethylthio Reagents for Enantioselective Trifluoromethylthiolation of Oxindoles. Org Lett 2014; 16:2192-5. [DOI: 10.1021/ol5006888] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Xing-Li Zhu
- Department of Chemistry, South University of Science and Technology of China, Shenzhen 518055, P. R. China
| | - Jin-Hui Xu
- Department of Chemistry, South University of Science and Technology of China, Shenzhen 518055, P. R. China
| | - Dao-Juan Cheng
- Department of Chemistry, South University of Science and Technology of China, Shenzhen 518055, P. R. China
| | - Li-Jiao Zhao
- Department of Chemistry, South University of Science and Technology of China, Shenzhen 518055, P. R. China
| | - Xin-Yuan Liu
- Department of Chemistry, South University of Science and Technology of China, Shenzhen 518055, P. R. China
| | - Bin Tan
- Department of Chemistry, South University of Science and Technology of China, Shenzhen 518055, P. R. China
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194
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A highly regio- and enantioselective organocatalyzed Michael addition of malonates to nitrodienes. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.tetasy.2014.02.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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195
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Zheng S, Schienebeck CM, Zhang W, Wang HY, Tang W. Cinchona Alkaloids as Organocatalysts in Enantioselective Halofunctionalization of Alkenes and Alkynes. ASIAN J ORG CHEM 2014. [DOI: 10.1002/ajoc.201400030] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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196
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Zhao Y, Wang XJ, Lin Y, Cai CX, Liu JT. Highly enantioselective direct Michael addition of 1,3-dicarbonyl compounds to β-fluoroalkyl-α-nitroalkenes. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.02.062] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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197
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New class of bifunctional thioureas from l-proline: highly enantioselective Michael addition of 1,3-dicarbonyls to nitroolefins. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.tetasy.2014.02.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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198
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Li N, Liu GG, Chen J, Pan FF, Wu B, Wang XW. Regio- and Enantioselective Organocascade Michael-Michael Reactions: Construction of Chiral Trisubstituted Indanes. European J Org Chem 2014. [DOI: 10.1002/ejoc.201301860] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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199
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Kótai B, Kardos G, Hamza A, Farkas V, Pápai I, Soós T. On the mechanism of bifunctional squaramide-catalyzed organocatalytic Michael addition: a protonated catalyst as an oxyanion hole. Chemistry 2014; 20:5631-9. [PMID: 24677388 DOI: 10.1002/chem.201304553] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2013] [Indexed: 12/31/2022]
Abstract
A joint experimental-theoretical study of a bifunctional squaramide-amine-catalyzed Michael addition reaction between 1,3-dioxo nucleophiles and nitrostyrene has been undertaken to gain insight into the nature of bifunctional organocatalytic activation. For this highly stereoselective reaction, three previously proposed mechanistic scenarios for the critical CC bond-formation step were examined. Accordingly, the formation of the major stereoisomeric products is most plausible by one of the bifunctional pathways that involve electrophile activation by the protonated amine group of the catalyst. However, some of the minor product isomers are also accessible through alternative reaction routes. Structural analysis of transition states points to the structural invariance of certain fragments of the transition state, such as the protonated catalyst and the anionic fragment of approaching reactants. Our topological analysis provides deeper insight and a more general understanding of bifunctional noncovalent organocatalysis.
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Affiliation(s)
- Bianka Kótai
- Institute of Organic Chemistry, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Pusztaszeri út 59-67, H-1025 Budapest (Hungary), Fax: (+36) 1-438-1145
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200
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Horitsugi N, Kojima K, Yasui K, Sohtome Y, Nagasawa K. Asymmetric Michael Reaction of Nitroolefins with β-Dicarbonyl Compounds Catalysed by 1,3-Diamine-Tethered Guanidine-Thiourea Bifunctional Organocatalysts. ASIAN J ORG CHEM 2014. [DOI: 10.1002/ajoc.201402002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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