151
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Fan YY, Gao XH, Yue JM. Attractive natural products with strained cyclopropane and/or cyclobutane ring systems. Sci China Chem 2016. [DOI: 10.1007/s11426-016-0233-1] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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152
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Zheng WF, Bora PP, Sun GJ, Kang Q. Rhodium-Catalyzed Regio- and Stereoselective [2 + 2] Cycloaddition of Allenamides. Org Lett 2016; 18:3694-7. [PMID: 27403894 DOI: 10.1021/acs.orglett.6b01731] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A highly regio- and stereoselective Rh-catalyzed intermolecular head-to-head [2 + 2] cycloaddition of allenamides was developed. The intermolecular cycloadducts, trans-dimethylenecyclobutane-1,2-diamine derivatives, were achieved in good yields with high regioselectivity and stereoselectivity.
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Affiliation(s)
- Wei-Feng Zheng
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West, Fuzhou 350002, China.,College of Materials Science and Engineering, Fujian Normal University , Fuzhou 350007, China
| | - Pranjal Protim Bora
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West, Fuzhou 350002, China
| | - Gui-Jun Sun
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West, Fuzhou 350002, China
| | - Qiang Kang
- Key Laboratory of Coal to Ethylene Glycol and Its Related Technology, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences , 155 Yangqiao Road West, Fuzhou 350002, China
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153
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Clay A, Vallavoju N, Krishnan R, Ugrinov A, Sivaguru J. Metal-Free Visible Light-Mediated Photocatalysis: Controlling Intramolecular [2 + 2] Photocycloaddition of Enones through Axial Chirality. J Org Chem 2016; 81:7191-200. [DOI: 10.1021/acs.joc.6b01066] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Anthony Clay
- Department of Chemistry and
Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Nandini Vallavoju
- Department of Chemistry and
Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Retheesh Krishnan
- Department of Chemistry and
Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Angel Ugrinov
- Department of Chemistry and
Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
| | - Jayaraman Sivaguru
- Department of Chemistry and
Biochemistry, North Dakota State University, Fargo, North Dakota 58108, United States
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154
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Colomer I, Batchelor-McAuley C, Odell B, Donohoe TJ, Compton RG. Hydrogen Bonding to Hexafluoroisopropanol Controls the Oxidative Strength of Hypervalent Iodine Reagents. J Am Chem Soc 2016; 138:8855-61. [DOI: 10.1021/jacs.6b04057] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Ignacio Colomer
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Christopher Batchelor-McAuley
- Department
of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Barbara Odell
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Timothy J. Donohoe
- Department
of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Richard G. Compton
- Department
of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
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155
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Direct Metal-Free Entry to Aminocyclobutenes or Aminocyclobutenols from Ynamides: Synthetic Applications. Chemistry 2016; 22:8998-9005. [DOI: 10.1002/chem.201601044] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Indexed: 01/28/2023]
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156
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Nielsen AJ, Jenkins HA, McNulty J. Asymmetric Organocatalytic Stepwise [2+2] Entry to Tetra-Substituted Heterodimeric and Homochiral Cyclobutanes. Chemistry 2016; 22:9111-5. [PMID: 27124364 DOI: 10.1002/chem.201601842] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Alex J. Nielsen
- Department of Chemistry and Chemical-Biology; McMaster University; 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
| | - Hilary A. Jenkins
- Department of Chemistry and Chemical-Biology; McMaster University; 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
| | - James McNulty
- Department of Chemistry and Chemical-Biology; McMaster University; 1280 Main Street West Hamilton Ontario L8S 4M1 Canada
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157
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Qiu Y, Yang B, Zhu C, Bäckvall JE. Palladium-Catalyzed Oxidative Carbocyclization-Borylation of Enallenes to Cyclobutenes. Angew Chem Int Ed Engl 2016; 55:6520-4. [PMID: 27088425 PMCID: PMC5021125 DOI: 10.1002/anie.201601613] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2016] [Indexed: 01/04/2023]
Abstract
A highly efficient palladium-catalyzed oxidative borylation of enallenes was developed for the selective formation of cyclobutene derivatives and fully-substituted alkenylboron compounds. Cyclobutenes are formed as the exclusive products in MeOH in the presence of H2 O and Et3 N, whereas the use of AcOH leads to alkenylboron compounds. Both reactions showed a broad substrate scope and good tolerance for various functional groups, including carboxylic acid ester, free hydroxy, imide, and alkyl groups. Furthermore, transformations of the borylated products were conducted to show their potential applications.
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Affiliation(s)
- Youai Qiu
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691, Stockholm, Sweden
| | - Bin Yang
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691, Stockholm, Sweden
| | - Can Zhu
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691, Stockholm, Sweden.
| | - Jan-E Bäckvall
- Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, 10691, Stockholm, Sweden.
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158
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Synthesis and analgesic activity of new α-truxillic acid derivatives with monoterpenoid fragments. Med Chem Res 2016. [DOI: 10.1007/s00044-016-1593-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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159
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Kang T, Ge S, Lin L, Lu Y, Liu X, Feng X. A Chiral
N
,
N′
‐Dioxide–Zn
II
Complex Catalyzes the Enantioselective [2+2] Cycloaddition of Alkynones with Cyclic Enol Silyl Ethers. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201600801] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Affiliation(s)
- Tengfei Kang
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Shulin Ge
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Lili Lin
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Yan Lu
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
- Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China
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160
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Qiu Y, Yang B, Zhu C, Bäckvall JE. Palladium-Catalyzed Oxidative Carbocyclization-Borylation of Enallenes to Cyclobutenes. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601613] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Youai Qiu
- Department of Organic Chemistry, Arrhenius Laboratory; Stockholm University; 10691 Stockholm Sweden
| | - Bin Yang
- Department of Organic Chemistry, Arrhenius Laboratory; Stockholm University; 10691 Stockholm Sweden
| | - Can Zhu
- Department of Organic Chemistry, Arrhenius Laboratory; Stockholm University; 10691 Stockholm Sweden
| | - Jan-E. Bäckvall
- Department of Organic Chemistry, Arrhenius Laboratory; Stockholm University; 10691 Stockholm Sweden
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161
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Panish RA, Chintala SR, Fox JM. A Mixed-Ligand Chiral Rhodium(II) Catalyst Enables the Enantioselective Total Synthesis of Piperarborenine B. Angew Chem Int Ed Engl 2016; 55:4983-7. [PMID: 26991451 PMCID: PMC4900183 DOI: 10.1002/anie.201600766] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Indexed: 12/19/2022]
Abstract
A novel, mixed-ligand chiral rhodium(II) catalyst, Rh2(S-NTTL)3(dCPA), has enabled the first enantioselective total synthesis of the natural product piperarborenine B. A crystal structure of Rh2(S-NTTL)3(dCPA) reveals a "chiral crown" conformation with a bulky dicyclohexylphenyl acetate ligand and three N-naphthalimido groups oriented on the same face of the catalyst. The natural product was prepared on large scale using rhodium-catalyzed bicyclobutanation/ copper-catalyzed homoconjugate addition chemistry in the key step. The route proceeds in ten steps with an 8% overall yield and 92% ee.
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Affiliation(s)
- Robert A Panish
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | - Srinivasa R Chintala
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA
| | - Joseph M Fox
- Department of Chemistry and Biochemistry, University of Delaware, Newark, DE, 19716, USA.
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162
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Kang T, Ge S, Lin L, Lu Y, Liu X, Feng X. A Chiral
N
,
N′
‐Dioxide–Zn
II
Complex Catalyzes the Enantioselective [2+2] Cycloaddition of Alkynones with Cyclic Enol Silyl Ethers. Angew Chem Int Ed Engl 2016; 55:5541-4. [DOI: 10.1002/anie.201600801] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Indexed: 12/20/2022]
Affiliation(s)
- Tengfei Kang
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Shulin Ge
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Lili Lin
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Yan Lu
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Xiaohua Liu
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
| | - Xiaoming Feng
- Key Laboratory of Green Chemistry & Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 China
- Collaborative Innovation Center of Chemical Science and Engineering Tianjin 300072 China
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163
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Panish RA, Chintala SR, Fox JM. A Mixed‐Ligand Chiral Rhodium(II) Catalyst Enables the Enantioselective Total Synthesis of Piperarborenine B. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201600766] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Robert A. Panish
- Department of Chemistry and Biochemistry University of Delaware Newark DE 19716 USA
| | | | - Joseph M. Fox
- Department of Chemistry and Biochemistry University of Delaware Newark DE 19716 USA
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164
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Colomer I, Coura Barcelos R, Donohoe TJ. Catalytic Hypervalent Iodine Promoters Lead to Styrene Dimerization and the Formation of Tri- and Tetrasubstituted Cyclobutanes. Angew Chem Int Ed Engl 2016; 55:4748-52. [DOI: 10.1002/anie.201511683] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 01/26/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Ignacio Colomer
- Department of Chemistry; University of Oxford; Chemistry Research Laboratory; Mansfield Road Oxford OX1 3TA UK
| | - Rosimeire Coura Barcelos
- Department of Chemistry; University of Oxford; Chemistry Research Laboratory; Mansfield Road Oxford OX1 3TA UK
| | - Timothy J. Donohoe
- Department of Chemistry; University of Oxford; Chemistry Research Laboratory; Mansfield Road Oxford OX1 3TA UK
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165
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Flores R, Font J, Alibés R, Figueredo M. A Study on the Photoreaction of 2(5H)-Furanones with Substituted Acetylenes: Evidence for a Mechanistic Reformulation. Chemistry 2016; 22:3835-45. [PMID: 26749319 DOI: 10.1002/chem.201503888] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Indexed: 11/07/2022]
Abstract
The photoreaction of 2(5H)-furanones with alkynes has been investigated. The complexity of this process is evidenced by the variety of isolated products, which have allowed disclosing interesting mechanistic aspects. When the reaction is performed in acetonitrile under direct excitation, in addition to the primary [2+2] cycloadducts, products derived from an 1,3-acyl shift rearrangement are also formed. For unsymmetrical alkynes, the rearrangement of the head-to-tail primary adducts produces new regioisomers and, when the starting furanone is chiral, this rearrangement inverts the relative anti/syn geometry of the primary cycloadducts. In the reactions performed in acetone under photosensitized conditions, rearranged products were never detected, supporting that the 1,3-acyl shift takes place from the singlet excited state S1 of the β,γ-unsaturated lactone. When bis(trimethylsilyl)acetylene is used as the alkyne partner, the major photoproducts are monocyclic bis(trimethylsilyl)lactones.
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Affiliation(s)
- Ramon Flores
- Departament de Química, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Josep Font
- Departament de Química, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain
| | - Ramon Alibés
- Departament de Química, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
| | - Marta Figueredo
- Departament de Química, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
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166
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Colomer I, Coura Barcelos R, Donohoe TJ. Catalytic Hypervalent Iodine Promoters Lead to Styrene Dimerization and the Formation of Tri‐ and Tetrasubstituted Cyclobutanes. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201511683] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Ignacio Colomer
- Department of Chemistry University of Oxford Chemistry Research Laboratory Mansfield Road Oxford OX1 3TA UK
| | - Rosimeire Coura Barcelos
- Department of Chemistry University of Oxford Chemistry Research Laboratory Mansfield Road Oxford OX1 3TA UK
| | - Timothy J. Donohoe
- Department of Chemistry University of Oxford Chemistry Research Laboratory Mansfield Road Oxford OX1 3TA UK
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167
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Sequential oxidation/thermal induced intramolecular [2+2] cycloaddition of propynol-vinylidenecyclopropanes: access to novel cyclobutene-containing spiro[2.3]hexenes. Tetrahedron 2016. [DOI: 10.1016/j.tet.2015.11.064] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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168
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A theoretical study on intermolecular [2+2] radical cation cycloaddition reactions and the competition between concerted and stepwise mechanisms. COMPUT THEOR CHEM 2016. [DOI: 10.1016/j.comptc.2016.01.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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169
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Nguyen N, Clements AR, Pattabiraman M. Using non-covalent interactions to direct regioselective 2+2 photocycloaddition within a macrocyclic cavitand. NEW J CHEM 2016. [DOI: 10.1039/c5nj02376a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A cavitand mediated approach involving host–guest and guest–guest interactions has been developed to direct regioselective photocycloaddition of non-symmetric alkenes wherein a complete reversal in selectivity is achievable.
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Affiliation(s)
- Nga Nguyen
- Department of Chemistry
- University of Nebraska Kearney
- Kearney
- USA
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170
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Sheikh NS. Captodative substitution induced acceleration effect towards 4π electrocyclic ring-opening of substituted cyclobutenes. RSC Adv 2016. [DOI: 10.1039/c5ra26590h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Significance of quantum chemical calculations as a theoretical tool to identify the optimum substitution pattern for a rapid 4π electrocyclic ring-opening of substituted cyclobutenes is presented.
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Affiliation(s)
- Nadeem S. Sheikh
- Department of Chemistry
- Faculty of Science
- King Faisal University
- Al-Ahsa 31982
- Saudi Arabia
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171
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Nguyen TB, Al-Mourabit A. Remarkably high homoselectivity in [2 + 2] photodimerization of trans-cinnamic acids in multicomponent systems. Photochem Photobiol Sci 2016; 15:1115-1119. [PMID: 27459036 DOI: 10.1039/c6pp00201c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
[2 + 2] homoadducts were exclusively obtained with total regio- and stereo-selectivities when a suspension of several solid photoactive trans-cinnamic acids in cyclohexane was stirred and irradiated.
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Affiliation(s)
- Thanh Binh Nguyen
- Institut de Chimie des Substances Naturelles
- CNRS UPR 2301
- Université Paris-Sud
- Université Paris-Saclay
- 91198 Gif-sur-Yvette
| | - Ali Al-Mourabit
- Institut de Chimie des Substances Naturelles
- CNRS UPR 2301
- Université Paris-Sud
- Université Paris-Saclay
- 91198 Gif-sur-Yvette
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172
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Fructos MR, Prieto A. [2+2] Cycloaddition reactions promoted by group 11 metal-based catalysts. Tetrahedron 2016. [DOI: 10.1016/j.tet.2015.11.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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173
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Sheikh NS. 4π electrocyclisation in domino processes: contemporary trends and synthetic applications towards natural products. Org Biomol Chem 2015; 13:10774-96. [PMID: 26440536 DOI: 10.1039/c5ob01703c] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Recent most instructive and reliable literature reports which deal with domino processes involving conrotatory 4π electrocyclic reactions, along with a precise mechanistic insight and latest synthetic applications towards biologically active natural products are concisely reviewed. To inspire further research in this domain, a real insight into the overarching emerging themes and potential imminent prospects is also provided.
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Affiliation(s)
- Nadeem S Sheikh
- Department of Chemistry, Faculty of Science, King Faisal University, P.O. Box 380, Al-Ahsa 31982, Saudi Arabia.
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174
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Yang S, Yuan W, Xu Q, Shi M. Iron(III)‐Catalyzed Cycloisomerizations of Acetal–Vinylidenecyclopropanes: An Efficient Synthetic Route to 1,2‐Disubstituted Cyclobutenes. Chemistry 2015; 21:15964-9. [PMID: 26383049 DOI: 10.1002/chem.201502634] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Indexed: 01/02/2023]
Affiliation(s)
- Song Yang
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Meilong Road No. 130, Shanghai, 200237 (P. R. China)
| | - Wei Yuan
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032 (P. R. China)
| | - Qin Xu
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Meilong Road No. 130, Shanghai, 200237 (P. R. China)
| | - Min Shi
- Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Meilong Road No. 130, Shanghai, 200237 (P. R. China)
- State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 354 Fenglin Road, Shanghai 200032 (P. R. China)
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175
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Xu Y, Conner ML, Brown MK. Cyclobutane and cyclobutene synthesis: catalytic enantioselective [2+2] cycloadditions. Angew Chem Int Ed Engl 2015; 54:11918-28. [PMID: 26333192 DOI: 10.1002/anie.201502815] [Citation(s) in RCA: 212] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Indexed: 12/21/2022]
Abstract
Cyclobutanes and cyclobutenes are important structural motifs found in numerous biologically significant molecules, and they are useful intermediates for chemical synthesis. Consequently, [2+2] cycloadditions to access cyclobutanes and cyclobutenes have been established to be particularly useful transformations. Within the last 10 years, an increase in the frequency of publications for catalytic enantioselective [2+2] cycloadditions has occurred. These reactions provide access to a wide array of enantiomerically enriched chemical diversity that was not previously attainable. Described in this review are the advances made in catalytic enantioselective [2+2] cycloadditions to access cyclobutanes and cyclobutenes.
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Affiliation(s)
- Yao Xu
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, IN 47405 (USA)
| | - Michael L Conner
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, IN 47405 (USA)
| | - M Kevin Brown
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, IN 47405 (USA).
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176
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Xu Y, Conner ML, Brown MK. Synthese von Cyclobutanen und Cyclobutenen: katalytische enantioselektive [2+2]-Cycloadditionen. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201502815] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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177
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Schmidt VA, Hoyt JM, Margulieux GW, Chirik PJ. Cobalt-Catalyzed [2π + 2π] Cycloadditions of Alkenes: Scope, Mechanism, and Elucidation of Electronic Structure of Catalytic Intermediates. J Am Chem Soc 2015; 137:7903-14. [PMID: 26030841 PMCID: PMC5633266 DOI: 10.1021/jacs.5b04034] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
![]()
Aryl-substituted bis(imino)pyridine
cobalt dinitrogen compounds,
(RPDI)CoN2, are effective precatalysts for the
intramolecular [2π + 2π] cycloaddition of α,ω-dienes
to yield the corresponding bicyclo[3.2.0]heptane derivatives. The
reactions proceed under mild thermal conditions with unactivated alkenes,
tolerating both amine and ether functional groups. The overall second
order rate law for the reaction, first order with respect to both
the cobalt precatalyst and the substrate, in combination with electron
paramagnetic resonance (EPR) spectroscopic studies established the
catalyst resting state as dependent on the identity of the precatalyst
and diene substrate. Planar S =1/2 κ3-bis(imino)pyridine cobalt alkene and
tetrahedral κ2-bis(imino)pyridine cobalt diene complexes
were observed by EPR spectroscopy and in the latter case structurally
characterized. The hemilabile chelate facilitates conversion of a
principally ligand-based singly occupied molecular orbital (SOMO)
in the cobalt dinitrogen and alkene compounds to a metal-based SOMO
in the diene intermediates, promoting C–C bond-forming oxidative
cyclization. Structure–activity relationships on bis(imino)pyridine
substitution were also established with 2,4,6-tricyclopentyl-substituted
aryl groups, resulting in optimized catalytic [2π + 2π]
cycloaddition. The cyclopentyl groups provide a sufficiently open
metal coordination sphere that encourages substrate coordination while
remaining large enough to promote a challenging, turnover-limiting
C(sp3)–C(sp3) reductive elimination.
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Affiliation(s)
- Valerie A Schmidt
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Jordan M Hoyt
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Grant W Margulieux
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Paul J Chirik
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
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178
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Melis N, Ghisu L, Guillot R, Caboni P, Secci F, Aitken DJ, Frongia A. Catalytic Enantioselective Synthesis of α-(Benzylamino)cyclobutanones. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500460] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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179
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Halskov KS, Kniep F, Lauridsen VH, Iversen EH, Donslund BS, Jørgensen KA. Organocatalytic enamine-activation of cyclopropanes for highly stereoselective formation of cyclobutanes. J Am Chem Soc 2015; 137:1685-91. [PMID: 25575040 DOI: 10.1021/ja512573q] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A novel organocatalytic activation mode of cyclopropanes is presented. The reaction concept is based on a design in which a reactive donor-acceptor cyclopropane intermediate is generated by in situ condensation of cyclopropylacetaldehydes with an aminocatalyst. The mechanism of this enamine-based activation of cyclopropylacetaldehydes is investigated by the application of a combined computational and experimental approach. The activation can be traced to a favorable orbital interaction between the π-orbital of the enamine and the σ*C-C orbital of the cyclopropyl ring. Furthermore, the synthetic potential of the developed system has been evaluated. By the application of a chiral secondary amine catalyst, the organocatalytically activated cyclopropanes show an unexpected and highly stereoselective formation of cyclobutanes, functionalizing at the usually inert sites of the donor-acceptor cyclopropane. By the application of 3-olefinic oxindoles and benzofuranone, biologically relevant spirocyclobutaneoxindoles and spirocyclobutanebenzofuranone can be obtained in good yields, high diastereomeric ratios, and excellent enantiomeric excesses. The mechanism of the reaction is discussed and two mechanistic proposals are presented.
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Affiliation(s)
- Kim Søholm Halskov
- Center for Catalysis, Department of Chemistry, Aarhus University , DK-8000 Aarhus C, Denmark
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180
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Dembitsky VM, Gloriozova TA, Poroikov VV. Naturally occurring plant isoquinoline N-oxide alkaloids: their pharmacological and SAR activities. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2015; 22:183-202. [PMID: 25636889 DOI: 10.1016/j.phymed.2014.11.002] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Revised: 09/21/2014] [Accepted: 11/12/2014] [Indexed: 05/28/2023]
Abstract
The present review describes research on novel natural isoquinoline alkaloids and their N-oxides isolated from different plant species. More than 200 biological active compounds have shown confirmed antimicrobial, antibacterial, antitumor, and other activities. The structures, origins, and reported biological activities of a selection of isoquinoline N-oxides alkaloids are reviewed. With the computer program PASS some additional SAR (structure-activity relationship) activities are also predicted, which point toward new possible applications of these compounds. This review emphasizes the role of isoquinoline N-oxides alkaloids as an important source of leads for drug discovery.
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Affiliation(s)
| | - Tatyana A Gloriozova
- Institute of Biomedical Chemistry, Russian Academy of the Medical Sciences, Moscow 119121, Russia
| | - Vladimir V Poroikov
- Institute of Biomedical Chemistry, Russian Academy of the Medical Sciences, Moscow 119121, Russia
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181
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Chen YJ, Hu TJ, Feng CG, Lin GQ. Synthesis of chiral cyclobutanes via rhodium/diene-catalyzed asymmetric 1,4-addition: a dramatic ligand effect on the diastereoselectivity. Chem Commun (Camb) 2015; 51:8773-6. [DOI: 10.1039/c5cc02023a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A highly diastereo- and enantioselective rhodium-catalyzed arylation of cyclobutene-1-carboxylate esters for the efficient synthesis of chiral cyclobutanes has been developed.
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Affiliation(s)
- Ya-Jing Chen
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- P. R. China
| | - Tian-Jiao Hu
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- P. R. China
| | - Chen-Guo Feng
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- P. R. China
| | - Guo-Qiang Lin
- CAS Key Laboratory of Synthetic Chemistry of Natural Substances
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- P. R. China
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182
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Liang R, Jiang H, Zhu S. An efficient route to highly strained cyclobutenes: indium-catalyzed reactions of enynals with alkynes. Chem Commun (Camb) 2015; 51:5530-3. [DOI: 10.1039/c4cc08506j] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A catalytic method to synthesize the highly strained cyclobutene was developed. The reaction was believed to proceed through a formal indium-catalyzed [2+2] cycloaddition between electron-deficient enynals and a variety of alkynes.
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Affiliation(s)
- Renxiao Liang
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou City
- China
| | - Huanfeng Jiang
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou City
- China
| | - Shifa Zhu
- School of Chemistry and Chemical Engineering
- South China University of Technology
- Guangzhou City
- China
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183
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Enomoto K, Oyama H, Nakada M. Highly Enantioselective Catalytic Asymmetric [2+2] Cycloadditions of Cyclic α-Alkylidene β-Oxo Imides with Ynamides. Chemistry 2014; 21:2798-802. [DOI: 10.1002/chem.201406189] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2014] [Indexed: 11/08/2022]
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184
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Qi LW, Yang Y, Gui YY, Zhang Y, Chen F, Tian F, Peng L, Wang LX. Asymmetric synthesis of 3,3'-spirooxindoles fused with cyclobutanes through organocatalytic formal [2 + 2] cycloadditions under H-bond-directing dienamine activation. Org Lett 2014; 16:6436-9. [PMID: 25494171 DOI: 10.1021/ol503266q] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The first organocatalytic asymmetric synthesis of a spirooxindole skeleton incorporated with a cyclobutane moiety has been successfully developed on the basis of H-bond-directing dienamine activation. Structurally complex spirocyclobutyl oxindoles, which possess four contiguous stereocenters, including one spiro quaternary center, were obtained in good yields (up to 83%) with excellent β,γ-regioselectivity (>19:1) and stereocontrol (up to >19:1 dr and 97% ee).
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Affiliation(s)
- Liang-Wen Qi
- Key Laboratory of Asymmetric Synthesis and Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences , Chengdu 610041, China
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185
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Chen S, Shan G, Nie P, Rao Y. 3-Alkyloxycyclobutanones as Useful Synthons for Heterocycle and Carbocycle Synthesis. ASIAN J ORG CHEM 2014. [DOI: 10.1002/ajoc.201402200] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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186
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Bernal-Albert P, Faustino H, Gimeno A, Asensio G, Mascareñas JL, López F. Gold(I)-catalyzed intermolecular cycloaddition of allenamides with α,β-unsaturated hydrazones: efficient access to highly substituted cyclobutanes. Org Lett 2014; 16:6196-9. [PMID: 25406491 PMCID: PMC4304836 DOI: 10.1021/ol503121q] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
α,β-Unsaturated N,N-dialkyl hydrazones undergo a mild [2 + 2] cycloaddition to allenamides when treated with a suitable gold catalyst. The method, which represents the first application of N,N-dialkyl hydrazones in gold catalysis, is compatible with a wide variety of substituents at the alkenyl moiety of the hydrazone component, proceeds with excellent levels of regio- and diastereoselectivity, and provides densely substituted cyclobutanes with good to excellent yields.
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Affiliation(s)
- Paloma Bernal-Albert
- Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CIQUS) and Departamento de Química Orgánica, Universidad de Santiago de Compostela , 15782, Santiago de Compostela, Spain
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187
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Kim KH, Lim JW, Lee J, Go MJ, Kim JN. Thermal Intramolecular [2+2] Cycloaddition: Synthesis of 3-Azabicyclo[3.1.1]heptanes from Morita-Baylis-Hillman Adduct-Derived 4,4-Diaryl-1,3-dienes. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201400571] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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188
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Li D, Rao W, Tay GL, Ayers BJ, Chan PWH. Gold-catalyzed cycloisomerization of 1,6-diyne esters to 1H-cyclopenta[b]naphthalenes, cis-cyclopenten-2-yl δ-diketones, and bicyclo[3.2.0]hepta-1,5-dienes. J Org Chem 2014; 79:11301-15. [PMID: 25263810 DOI: 10.1021/jo5020195] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A synthetic method to chemoselectively prepare 1H-cyclopenta[b]naphthalenes, cis-cyclopenten-2-yl δ-diketones, and bicyclo[3.2.0]hepta-1,5-dienes efficiently by gold-catalyzed cycloisomerization of 1,6-diyne esters is described. These three product classes were accessed divergently by taking advantage of the electronic and steric differences between a phosphine and NHC (NHC = N-heterocyclic carbene) ligand in the respective gold(I) complexes and that of gold(III) complex combined with substrate substitution patterns and optimized reaction conditions. In the presence of [PhCNAuIPr](+)SbF6(-) (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidine) as the catalyst, substrates with a pendant aryl group at the acetate alkynyl position were found to undergo preferential 1,3-acyloxy migration/5-exo-dig cyclization/Friedel-Crafts reaction to give 1H-cyclopenta[b]naphthalenes. In contrast, the analogous reactions with PicAuCl2 (Pic =2-picolinate) were found to proceed by selective 1,3-acyloxy migration/5-exo-dig cyclization/1,5-acyl migration to afford cis-cyclopenten-2-yl δ-diketones. Changing the catalyst to [MeCNAu(JohnPhos)](+)SbF6(-) (JohnPhos = (1,1'-biphenyl-2-yl)-di-tert-butylphosphine) and the acetate alkynyl position from an aryl to vinyl substituent in the starting ester led to 1,3-acyloxy migration/5-exo-dig cyclization/Prins-type [2 + 2]-cycloaddition to provide bicyclo[3.2.0]hepta-1,5-dienes.
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Affiliation(s)
- Dan Li
- School of Chemistry, Monash University , Clayton 3800, Victoria, Australia
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189
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Dembitsky VM. Naturally occurring bioactive Cyclobutane-containing (CBC) alkaloids in fungi, fungal endophytes, and plants. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2014; 21:1559-1581. [PMID: 25442265 DOI: 10.1016/j.phymed.2014.07.005] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 06/03/2014] [Accepted: 07/02/2014] [Indexed: 05/28/2023]
Abstract
This article focuses on the occurrence and biological activities of cyclobutane-containing (CBC) alkaloids obtained from fungi, fungal endophytes, and plants. Naturally occurring CBC alkaloids are of particular interest because many of these compounds display important biological activities and possess antitumour, antibacterial, antimicrobial, antifungal, and immunosuppressive properties. Therefore, these compounds are of great interest in the fields of medicine, pharmacology, medicinal chemistry, and the pharmaceutical industry. Fermentation and production of CBC alkaloids by fungi and/or fungal endophytes is also discussed. This review presents the structures and describes the activities of 98 CBC alkaloids.
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Affiliation(s)
- Valery M Dembitsky
- Institute of Drug Discovery, Har-Hotsvim, P.O. Box 45289, Jerusalem 91451, Israel.
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190
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Johnson T, Choo KL, Lautens M. Rhodium-Catalyzed Arylative Cyclization for the Enantioselective Synthesis of (Trifluoromethyl)cyclobutanols. Chemistry 2014; 20:14194-7. [DOI: 10.1002/chem.201404896] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Indexed: 11/09/2022]
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191
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Murakami R, Tsunoda K, Iwai T, Sawamura M. Stereoselective CH Borylations of Cyclopropanes and Cyclobutanes with Silica-Supported Monophosphane-Ir Catalysts. Chemistry 2014; 20:13127-31. [DOI: 10.1002/chem.201404362] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Indexed: 01/16/2023]
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192
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Hernvann F, Rasore G, Declerck V, Aitken DJ. Stereoselective intermolecular [2 + 2]-photocycloaddition reactions of maleic anhydride: stereocontrolled and regiocontrolled access to 1,2,3-trifunctionalized cyclobutanes. Org Biomol Chem 2014; 12:8212-22. [DOI: 10.1039/c4ob01383b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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193
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Hurtley AE, Lu Z, Yoon TP. [2+2] cycloaddition of 1,3-dienes by visible light photocatalysis. Angew Chem Int Ed Engl 2014; 53:8991-4. [PMID: 24985967 PMCID: PMC4134740 DOI: 10.1002/anie.201405359] [Citation(s) in RCA: 130] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Indexed: 11/08/2022]
Abstract
[2+2] photocycloadditions of 1,3-dienes represent a powerful yet synthetically underutilized class of reactions. We report that visible light absorbing transition metal complexes enable the [2+2] cycloaddition of a diverse range of 1,3-dienes. The ability to use long-wavelength visible light is attractive because these reaction conditions tolerate the presence of sensitive functional groups that might be readily decomposed by the high-energy UVC radiation required for direct photoexcitation of 1,3-dienes. The resulting vinylcyclobutane products are poised for a variety of further diversification reactions, and this method is consequently expected to be powerfully enabling in the synthesis of complex organic targets.
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Affiliation(s)
- Anna E. Hurtley
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue Madison, WI 53706, USA
| | - Zhan Lu
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue Madison, WI 53706, USA
| | - Tehshik P. Yoon
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue Madison, WI 53706, USA
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194
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Yuan Y, Bai L, Nan J, Liu J, Luan X. Regiospecific Ficini [2 + 2] cycloaddition of ynamides with cyclic isoimidium salts under catalyst-free conditions. Org Lett 2014; 16:4316-9. [PMID: 25102092 DOI: 10.1021/ol5020587] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The regiospecific [2 + 2] cycloaddition of cyclic isoimidium salts with ynamides is described. This effort led to the development of the first successful example of a catalyst-free, thermally driven Ficini [2 + 2] cycloaddition process of ynamides with α,β-unsaturated carbonyl compounds, giving the stable cyclobutenamides in excellent yields (up to 99%).
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Affiliation(s)
- Yini Yuan
- Key Laboratory of Synthetic and Natural Functional Molecular Chemistry of the Ministry of Education, College of Chemistry & Materials Science, Northwest University , Xi'an 710069, China
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195
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Hu YQ, Li C, Zhao BX, Li JY, Huang XJ, Lin J, Wang Y, Ye WC, Chen WM. Regioselective and stereoselective photodimerization of securinine-type and norsecurinine-type alkaloids. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.05.061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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196
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Hurtley AE, Lu Z, Yoon TP. [2+2] Cycloaddition of 1,3-Dienes by Visible Light Photocatalysis. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201405359] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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197
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Xiao KJ, Lin DW, Miura M, Zhu RY, Gong W, Wasa M, Yu JQ. Palladium(II)-catalyzed enantioselective C(sp³)-H activation using a chiral hydroxamic acid ligand. J Am Chem Soc 2014; 136:8138-42. [PMID: 24815880 PMCID: PMC4063184 DOI: 10.1021/ja504196j] [Citation(s) in RCA: 206] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
An enantioselective method for Pd(II)-catalyzed cross-coupling of methylene β-C(sp(3))-H bonds in cyclobutanecarboxylic acid derivatives with arylboron reagents is described. High yields and enantioselectivities were achieved through the development of chiral mono-N-protected α-amino-O-methylhydroxamic acid (MPAHA) ligands, which form a chiral complex with the Pd(II) center. This reaction provides an alternative approach to the enantioselective synthesis of cyclobutanecarboxylates containing α-chiral quaternary stereocenters. This new class of chiral catalysts also show promises for enantioselective β-C(sp(3))-H activation of acyclic amides.
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Affiliation(s)
- Kai-Jiong Xiao
- Department of Chemistry, The Scripps Research Institute , 10550 N. Torrey Pines Road, La Jolla, California 92037, United States
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198
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Gutekunst WR, Baran PS. Applications of C-H functionalization logic to cyclobutane synthesis. J Org Chem 2014; 79:2430-52. [PMID: 24548142 PMCID: PMC3985916 DOI: 10.1021/jo4027148] [Citation(s) in RCA: 150] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Indexed: 02/08/2023]
Abstract
The application of C-H functionalization logic to target-oriented synthesis provides an exciting new venue for the development of new and useful strategies in organic chemistry. In this article, C-H functionalization reactions are explored as an alternative approach to access pseudodimeric cyclobutane natural products, such as the dictazole and the piperarborenine families. The use of these strategies in a variety of complex settings highlights the subtle geometric, steric, and electronic effects at play in the auxiliary guided C-H functionalization of cyclobutanes.
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Affiliation(s)
- Will R. Gutekunst
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Phil S. Baran
- Department
of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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199
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Mao J, Bao W. Palladium-catalyzed [2+1+1] annulation of norbornenes with (z)-bromostyrenes: synthesis of bismethylenecyclobutanes via twofold C(sp2)–H bond activation. Chem Commun (Camb) 2014; 50:15726-9. [DOI: 10.1039/c4cc06545j] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A Pd(0)-catalyzed domino bismethylenecyclobutanation reaction was established. The [2+1+1] cycloaddition involves twofold C(sp2)–H bond activation and formation of three carbon–carbon bonds.
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Affiliation(s)
- Jiangang Mao
- Department of Chemistry
- Zhejiang University (Xixi Campus)
- Hangzhou 310028, People's Republic of China
- School of Metallurgy and Chemical Engineering
- Jiangxi University of Science and Technology
| | - Weiliang Bao
- Department of Chemistry
- Zhejiang University (Xixi Campus)
- Hangzhou 310028, People's Republic of China
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200
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A theoretical study on the competing mechanisms and regioselectivity of the intermolecular radical anion [2+2] cycloadditions of phenyl vinyl sulfone with enones. COMPUT THEOR CHEM 2014. [DOI: 10.1016/j.comptc.2013.11.026] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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