1
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Zhang Y, Chen Y, Song M, Tan B, Jiang Y, Yan C, Jiang Y, Hu X, Zhang C, Chen W, Xu J. Total Syntheses of Calyciphylline A-Type Alkaloids (-)-10-Deoxydaphnipaxianine A, (+)-Daphlongamine E and (+)-Calyciphylline R via Late-Stage Divinyl Carbinol Rearrangements. J Am Chem Soc 2022; 144:16042-16051. [PMID: 36007885 DOI: 10.1021/jacs.2c05957] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Among the famous Daphniphyllum alkaloids family, the calyciphylline A-type subfamily has triggered particular interest from the organic synthesis community in recent years. Here, we report divergent total syntheses of three calyciphylline A-type alkaloids, namely, (-)-10-deoxydaphnipaxianine A, (+)-daphlongamine E, and (+)-calyciphylline R. Our work highlights an efficient, divergent strategy via late-stage divinyl carbinol rearrangements, including an unprecedented oxidative Nazarov electrocyclization using an unfunctionalized tertiary divinyl carbinol and an unusual allylic alcohol rearrangement. A highly efficient "donor-acceptor" platinum catalyst was used for a critical nitrile hydration step. Moreover, the power of selective amide reductions has also been showcased by novel and classic tactics.
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Affiliation(s)
- Yan Zhang
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yuye Chen
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Manrong Song
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Bin Tan
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yujia Jiang
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chongyuan Yan
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Yuyang Jiang
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Xinyue Hu
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Chengqian Zhang
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Wenqing Chen
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
| | - Jing Xu
- Department of Chemistry and Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis and Shenzhen Key Laboratory of Small Molecule Drug Discovery and Synthesis, Southern University of Science and Technology, Shenzhen 518055, China
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2
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Abstract
The defining feature of the Nazarov cyclization is a 4π-conrotatory electrocyclization, resulting in the stereospecific formation of functionalized cyclopentanones. The reaction provides access to structural motifs that are found in many natural products and drug targets. Harnessing the full potential of the Nazarov cyclization broadens its utility by enabling the development of new methodologies and synthetic strategies. To achieve these goals through efficient cyclization design, it is helpful to think of the reaction as a two-stage process. The first stage involves a 4π-electrocyclization leading to the formation of an allylic cation, and the second stage corresponds to the fate of this cationic intermediate. With a complete understanding of the discrete events that characterize the overall process, one can optimize reactivity and control the selectivity of the different Stage 2 pathways.In this Account, we describe the development of methods that render the Nazarov cyclization catalytic and chemoselective, focusing specifically on advances made in our lab between 2002 and 2015. The initial discovery made in our lab involved reactions of electronically asymmetric ("polarized") substrates, which cyclize efficiently in the catalytic regime using mild Lewis acidic reagents. These cyclizations also exhibit selective eliminative behavior, increasing their synthetic utility. Research directed toward catalytic asymmetric Nazarov cyclization led to the serendipitous discovery of a 4π-cyclization coupled to a well-behaved Wagner-Meerwein rearrangement, representing an underexplored Stage 2 process. With careful choice of promoter and loading, it is possible to access either the rearrangement or the elimination pathway. Additional experimental and computational studies provided an effective model for anticipating the migratory behavior of substiutents in the rearrangements. Problem-solving efforts prompted investigation of alternative methods for generating pentadienyl cation intermediates, including oxidation of allenol ethers and addition of nucleophiles to dienyl diketones. These Nazarov cyclization variants afford cyclopentenone products with vicinal stereogenic centers and a different arrangement of substituents around the ring. A nucleophilic addition/cyclization/elimination sequence can be executed enantioselectively using catalytic amounts of a nonracemic chiral tertiary amine.In summary, the discovery and development of several new variations on the Nazarov electrocyclization are described, along with synthetic applications. This work illustrates how strongly substitution patterns can impact the efficiency of the 4π-electrocyclization (Stage 1), allowing for mild Lewis acid catalysis. Over the course of these studies, we have also identified new ways to access the critical pentadienyl cation intermediates and demonstrated strategies that exploit and control the different cationic pathways available post-electrocyclization (Stage 2 processes). These advances in Nazarov chemistry were subsequently employed in the synthesis of natural product targets such as (±)-merrilactone A, (±)-rocaglamide, and (±)-enokipodin B.
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Affiliation(s)
- Alison J. Frontier
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
| | - Jackson J. Hernandez
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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3
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Corbin JR, Ketelboeter DR, Fernández I, Schomaker JM. Biomimetic 2-Imino-Nazarov Cyclizations via Eneallene Aziridination. J Am Chem Soc 2020; 142:5568-5573. [PMID: 32142272 DOI: 10.1021/jacs.0c02441] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Amidoallyl cations are appealing three-carbon synthons for the preparation of complex amine-containing carbocycles; however, methods to generate and utilize these reactive species are limited and underexplored compared to those for oxallyl cations. Here we disclose a bioinspired strain-driven ring opening of bicyclic methyleneaziridines to 2-amidopentadienyl cation intermediates that readily engage in Nazarov cyclizations. Advantages of this strategy include ease of generation and improved reactivity compared to 3-pentadienyl cations, control over the ultimate position of the alkene, the potential for high dr between vicinal stereocenters, and the ability to further elaborate the products to fully substituted aminocyclopentanes. Experimental and computational studies support a dual role for the Rh2Ln complex as both a nitrene transfer catalyst and a Lewis acid promoter, insight that provides a framework for the future development of asymmetric 2-imino-Nazarov cyclizations.
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Affiliation(s)
- Joshua R Corbin
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Devin R Ketelboeter
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Israel Fernández
- Departmento de Quimíca Orgánica I and Centro de Innovación en Quimíca Avazanda (ORFEO-CINQA), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - Jennifer M Schomaker
- Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States
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4
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Bartko SG, Hamzik PJ, Espindola L, Gomez C, Danheiser RL. Synthesis of Highly Substituted Pyridines via [4 + 2] Cycloadditions of Vinylallenes and Sulfonyl Cyanides. J Org Chem 2020; 85:548-563. [PMID: 31797669 DOI: 10.1021/acs.joc.9b02628] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A convergent strategy for the synthesis of multisubstituted pyridines is described. Vinylallenes combine with commercially available arylsulfonyl cyanides in Diels-Alder cycloadditions to generate isopyridine cycloadducts that are converted to pyridines upon further heating or addition of a base. The 2-sulfonylpyridine products undergo nucleophilic aromatic substitution reactions with oxygen and carbon nucleophiles to provide access to a variety of highly substituted pyridines.
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Affiliation(s)
- Samuel G Bartko
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Phillip J Hamzik
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Leandro Espindola
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Christian Gomez
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
| | - Rick L Danheiser
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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5
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Abstract
Vinylallenes have been synthesized and used as reagents for many years. However,
the number of reviews covering the advances in the chemistry of vinylallenes are
scarce. Most of the information lies in general reviews about allenes or in reviews dedicated
to specific areas of research. Today, vinylallenes are used in the synthesis due to the
special characteristics of this moiety, a diene with a non-conjugated double bond and the
capacity to generate axial chirality. In this review, the most relevant publications
involving vinylallenes, published in the last fifteen years, are compiled. The review
includes new or improved synthetic methods and the reactivity of vinylallenes prepared by
classical or new methods. The reactions of vinylallenes have been classified as Nazarovtype
processes, cycloaddition reactions, and reactions in which vinylallenes are key
intermediates, usually non-isolated but essential for the process to occur. Other types of reactivity are also
included.
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Affiliation(s)
- María M. Afonso
- Departamento de Química Orgánica, Instituto Universitario de Bio-Orgánica Antonio González, Universidad de La Laguna, La Laguna, Spain
| | - J. Antonio Palenzuela
- Departamento de Química Orgánica, Instituto Universitario de Bio-Orgánica Antonio González, Universidad de La Laguna, La Laguna, Spain
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6
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Huang X, Thor W, Feng X, Kang L, Yang M, Lee CS, Cheng YK, He S. (4 + 3) cycloadditions of allenyl ether-derived oxygen-stabilized oxyallyls with furans. Org Chem Front 2020. [DOI: 10.1039/c9qo01349k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
(4 + 3) Cycloadditions between allenyl ethers and furans are described. The reaction features anin situformation of oxygen-stabilized oxyallylsviaepoxidations of allenyl ethers in the presence of H2PO4−.
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Affiliation(s)
- Xian Huang
- School of Pharmaceutical Sciences
- and Guizhou Engineering Laboratory for Synthetic Drugs
- Guizhou University
- Guiyang
- China
| | - Waygen Thor
- Department of Chemistry
- Hong Kong Baptist University
- Kowloon Tong
- Hong Kong SAR
| | - Xiangyu Feng
- School of Pharmaceutical Sciences
- and Guizhou Engineering Laboratory for Synthetic Drugs
- Guizhou University
- Guiyang
- China
| | - Liangliang Kang
- School of Pharmaceutical Sciences
- and Guizhou Engineering Laboratory for Synthetic Drugs
- Guizhou University
- Guiyang
- China
| | - Min Yang
- School of Pharmaceutical Sciences
- and Guizhou Engineering Laboratory for Synthetic Drugs
- Guizhou University
- Guiyang
- China
| | - Chi-Sing Lee
- Department of Chemistry
- Hong Kong Baptist University
- Kowloon Tong
- Hong Kong SAR
| | - Yuen-Kit Cheng
- Department of Chemistry
- Hong Kong Baptist University
- Kowloon Tong
- Hong Kong SAR
| | - Shuzhong He
- School of Pharmaceutical Sciences
- and Guizhou Engineering Laboratory for Synthetic Drugs
- Guizhou University
- Guiyang
- China
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7
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Gelozia S, Kwon Y, McDonald R, West FG. One-Pot Generation of Bicyclo[3.1.0]hexanols and Cyclohexanones by Double Interrupted Nazarov Reactions. Chemistry 2018; 24:6052-6056. [PMID: 29444379 DOI: 10.1002/chem.201800758] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Indexed: 12/20/2022]
Abstract
Organoaluminum-mediated double interrupted Nazarov cyclization to access bicyclo[3.1.0]hexanols via nucleophilic methyl attack followed by Simmons-Smith-type electrophilic cyclopropanation is reported. These alcohols can undergo ring opening to afford cyclohexanones or cyclohexenones, broadening the range of scaffolds available via interrupted Nazarov reaction beyond the usual cyclopentanoid products. Throughout the sequence, a total of four new C-C bonds are formed, along with four new stereogenic centers.
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Affiliation(s)
- Shorena Gelozia
- Department of Chemistry, University of Alberta, E3-43 Gunning-Lemieux Chemistry Centre, Edmonton, Alberta, T6G 2G2, Canada
| | - Yonghoon Kwon
- Department of Chemistry, University of Alberta, E3-43 Gunning-Lemieux Chemistry Centre, Edmonton, Alberta, T6G 2G2, Canada
| | - Robert McDonald
- Department of Chemistry, University of Alberta, E3-43 Gunning-Lemieux Chemistry Centre, Edmonton, Alberta, T6G 2G2, Canada
| | - F G West
- Department of Chemistry, University of Alberta, E3-43 Gunning-Lemieux Chemistry Centre, Edmonton, Alberta, T6G 2G2, Canada
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8
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Jolit A, Dickinson CF, Kitamura K, Walleser PM, Yap GPA, Tius MA. Catalytic Enantioselective Nazarov Cyclization. European J Org Chem 2017. [DOI: 10.1002/ejoc.201701117] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Anais Jolit
- Chemistry Department; University of Hawaii at Manoa; 2545 The Mall 96822 Honolulu HI USA
| | - Cody F. Dickinson
- Chemistry Department; University of Hawaii at Manoa; 2545 The Mall 96822 Honolulu HI USA
| | - Kei Kitamura
- Chemistry Department; University of Hawaii at Manoa; 2545 The Mall 96822 Honolulu HI USA
| | - Patrick M. Walleser
- Chemistry Department; University of Hawaii at Manoa; 2545 The Mall 96822 Honolulu HI USA
| | - Glenn P. A. Yap
- Department of Chemistry and Biochemistry; University of Delaware; 236 Brown Laboratory 19716 Newark DE USA
| | - Marcus A. Tius
- Chemistry Department; University of Hawaii at Manoa; 2545 The Mall 96822 Honolulu HI USA
- University of Hawaii Cancer Center; 701 Ilalo Street 96813 Honolulu HI USA
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9
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Fradette RJ, Kang M, West FG. Oxidation-Initiated Cyclizations of Pentadienyl Ethers: An Alternative Entry to the Nazarov Reaction. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201701748] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Ryan J. Fradette
- Department of Chemistry; University of Alberta; E3-43 Gunning-Lemieux Chemistry Centre; Edmonton AB T6G 2G2 Canada
| | - Minkyu Kang
- Department of Chemistry; University of Alberta; E3-43 Gunning-Lemieux Chemistry Centre; Edmonton AB T6G 2G2 Canada
| | - F. G. West
- Department of Chemistry; University of Alberta; E3-43 Gunning-Lemieux Chemistry Centre; Edmonton AB T6G 2G2 Canada
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10
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Fradette RJ, Kang M, West FG. Oxidation-Initiated Cyclizations of Pentadienyl Ethers: An Alternative Entry to the Nazarov Reaction. Angew Chem Int Ed Engl 2017; 56:6335-6338. [DOI: 10.1002/anie.201701748] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Ryan J. Fradette
- Department of Chemistry; University of Alberta; E3-43 Gunning-Lemieux Chemistry Centre; Edmonton AB T6G 2G2 Canada
| | - Minkyu Kang
- Department of Chemistry; University of Alberta; E3-43 Gunning-Lemieux Chemistry Centre; Edmonton AB T6G 2G2 Canada
| | - F. G. West
- Department of Chemistry; University of Alberta; E3-43 Gunning-Lemieux Chemistry Centre; Edmonton AB T6G 2G2 Canada
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11
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Vinogradov MG, Turova OV, Zlotin SG. Nazarov reaction: current trends and recent advances in the synthesis of natural compounds and their analogs. Org Biomol Chem 2017; 15:8245-8269. [DOI: 10.1039/c7ob01981e] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Recent applications of the Nazarov reaction to stereoselective synthesis of pharmacology-relevant cyclopentenone scaffolds are summarized.
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Affiliation(s)
- Maxim G. Vinogradov
- N.D. Zelinsky Institute of Organic Chemistry
- Russian Academy of Sciences
- 119991 Moscow
- Russian Federation
| | - Olga V. Turova
- N.D. Zelinsky Institute of Organic Chemistry
- Russian Academy of Sciences
- 119991 Moscow
- Russian Federation
| | - Sergei G. Zlotin
- N.D. Zelinsky Institute of Organic Chemistry
- Russian Academy of Sciences
- 119991 Moscow
- Russian Federation
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12
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William R, Wang S, Mallick A, Liu XW. Interrupting Nazarov Reaction with Different Trapping Modality: Utilizing Potassium Alkynyltrifluoroborate as a σ-Nucleophile. Org Lett 2016; 18:4458-61. [DOI: 10.1021/acs.orglett.6b01606] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ronny William
- Division
of Chemistry and
Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Siming Wang
- Division
of Chemistry and
Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Asadulla Mallick
- Division
of Chemistry and
Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Xue-Wei Liu
- Division
of Chemistry and
Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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13
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Sabbasani VR, Lee H, Xia Y, Lee D. Complementary Iron(II)‐Catalyzed Oxidative Transformations of Allenes with Different Oxidants. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201510006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Venkata R. Sabbasani
- Department of Chemistry University of Illinois at Chicago 845 West Taylor Street Chicago IL 60607 USA
| | - Hyunjin Lee
- Department of Chemistry University of Illinois at Chicago 845 West Taylor Street Chicago IL 60607 USA
| | - Yuanzhi Xia
- College of Chemistry and Materials Engineering Wenzhou University Wenzhou Zhejiang Province 325035 P.R. China
| | - Daesung Lee
- Department of Chemistry University of Illinois at Chicago 845 West Taylor Street Chicago IL 60607 USA
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14
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Sabbasani VR, Lee H, Xia Y, Lee D. Complementary Iron(II)‐Catalyzed Oxidative Transformations of Allenes with Different Oxidants. Angew Chem Int Ed Engl 2015; 55:1151-5. [PMID: 26636261 DOI: 10.1002/anie.201510006] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 11/10/2015] [Indexed: 12/16/2022]
Affiliation(s)
- Venkata R. Sabbasani
- Department of Chemistry University of Illinois at Chicago 845 West Taylor Street Chicago IL 60607 USA
| | - Hyunjin Lee
- Department of Chemistry University of Illinois at Chicago 845 West Taylor Street Chicago IL 60607 USA
| | - Yuanzhi Xia
- College of Chemistry and Materials Engineering Wenzhou University Wenzhou Zhejiang Province 325035 P.R. China
| | - Daesung Lee
- Department of Chemistry University of Illinois at Chicago 845 West Taylor Street Chicago IL 60607 USA
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15
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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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16
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Liu J, Liu Q, Franke R, Jackstell R, Beller M. Ligand-Controlled Palladium-Catalyzed Alkoxycarbonylation of Allenes: Regioselective Synthesis of α,β- and β,γ-Unsaturated Esters. J Am Chem Soc 2015; 137:8556-63. [DOI: 10.1021/jacs.5b04052] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jie Liu
- Leibniz-Institut
für Katalyse e.V., an der Universität Rostock, Albert-Einstein-Str.
29a, 18059 Rostock, Germany
| | - Qiang Liu
- Leibniz-Institut
für Katalyse e.V., an der Universität Rostock, Albert-Einstein-Str.
29a, 18059 Rostock, Germany
| | - Robert Franke
- Evonik Industries AG, Paul-Baumann-Str.
1, 45772 Marl, Germany
- Lehrstuhl für Theoretische Chemie, 44780 Bochum, Germany
| | - Ralf Jackstell
- Leibniz-Institut
für Katalyse e.V., an der Universität Rostock, Albert-Einstein-Str.
29a, 18059 Rostock, Germany
| | - Matthias Beller
- Leibniz-Institut
für Katalyse e.V., an der Universität Rostock, Albert-Einstein-Str.
29a, 18059 Rostock, Germany
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17
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De la Campa R, Flórez J. Water freezing as a regiocontrol element in the multicomponent assembly of cyclic enones. Chemistry 2015; 21:1854-9. [PMID: 25418199 DOI: 10.1002/chem.201404670] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Indexed: 11/10/2022]
Abstract
Regioselective synthesis of dialkoxy 2-cyclopentenones and 2-cyclohexenones with novel substitution patterns has been accomplished by the one-pot combination of three simple starting materials (chromium carbene complex, Weinreb acetamide lithium enolate and 1-alkoxyallenyllithium) under either anhydrous conditions or water-promoted solidification of the reaction mixture. These results revealed an unprecedented water-freezing effect that plays a key role to completely reverse the regioselectivity of the intramolecular carbometalation of an allene moiety.
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Affiliation(s)
- Raquel De la Campa
- Departamento de Química Orgánica e Inorgánica and Instituto Universitario de Química Organometálica "Enrique Moles", Universidad de Oviedo, Julián Clavería 8, 33006 Oviedo, Asturias (Spain), Fax: (+34) 985-103446
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18
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Daneshfar Z, Rostami A. Cellulose sulfonic acid as a green, efficient, and reusable catalyst for Nazarov cyclization of unactivated dienones and pyrazoline synthesis. RSC Adv 2015. [DOI: 10.1039/c5ra19773b] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A high yielding and eco-friendly procedure for the preparation of cyclopentenoid and pyrazoline derivatives via cellulose sulfonic acid-mediated electrocyclization processes.
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Affiliation(s)
- Zahra Daneshfar
- Department of Polymer Chemistry
- Faculty of Chemistry
- Shahid Beheshti University
- Tehran
- I. R. Iran
| | - Ali Rostami
- Department of Polymer Chemistry
- Faculty of Chemistry
- Shahid Beheshti University
- Tehran
- I. R. Iran
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19
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Zhu YP, Cai Q, Jia FC, Liu MC, Gao QH, Meng XG, Wu AX. Electronic tuning cyclization of aryl-1,4-enediones: AlCl3-mediated Nazarov-type cyclization to synthesize polysubstituted-1-indanones. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.10.052] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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20
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Affiliation(s)
| | | | - Tehshik P. Yoon
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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21
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Sousa CM, Berthet J, Delbaere S, Coelho PJ. Acid-catalyzed domino reactions of tetraarylbut-2-yne-1,4-diols. Synthesis of conjugated indenes and inden-2-ones. J Org Chem 2014; 79:5781-6. [PMID: 24846324 DOI: 10.1021/jo500907z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of tetraarylbut-2-yne-1,4-diols with electron-rich aromatic compounds at room temperature, under p-TsOH catalysis, affords substituted polycyclic aromatic indene derivatives through a domino reaction involving the formation of a cationic allenylium intermediate. This species can undergo a series of competitive intramolecular cascade reactions, leading to a conjugated inden-2-one. This simple method allows the efficient synthesis of substituted indenes and inden-2-ones, in two steps, from aromatic ketones.
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Affiliation(s)
- Céu M Sousa
- Centro de Quı́mica-Vila Real, Universidade de Trás-os-Montes e Alto Douro , 5000-801 Vila Real, Portugal
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22
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Abstract
Alkoxyallenes are unusually versatile C3 building blocks in organic synthesis. Hence this tutorial review summarizes the most important transformations, including subsequent reactions and their applications in the synthesis of relevant compounds, e.g. natural products. The reactivity patterns involved and the synthons derived from alkoxyallenes are presented. Often alkoxyallenes can serve as substitutes of acrolein or acrolein acetals, utilisation of which has already led to interesting products. Most important is the use of lithiated alkoxyallenes which smoothly react with a variety of electrophiles and lead to products with unique substitution patterns. The heterocycles or carbocycles formed are intermediates for the stereoselective synthesis of natural products or for the preparation of other structurally relevant compounds. The different synthons being put into practice by the use of lithiated alkoxyallenes in these variations will be discussed.
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Affiliation(s)
- Reinhold Zimmer
- Institut für Chemie und Biochemie, Freie Universität Berlin, Takustrasse 3, 14195 Berlin, Germany.
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Luo J, Zhou H, Hu J, Wang R, Tang Q. Efficient catalytic-free method to produce α-aryl cycloalkanones through highly chemoselective coupling of aryl compounds with oxyallyl cations. RSC Adv 2014. [DOI: 10.1039/c4ra01043d] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Efficient catalytic-free method to produce α-aryl cycloalkanones through highly chemoselective coupling of aryl compounds with oxyallyl cations at room temperature.
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Affiliation(s)
- Juan Luo
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
- College of Pharmacy
- Chongqing Medical University
- Chongqing 400016, P. R. China
- The Faculty of Laboratory Medicine
| | - Hui Zhou
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
- College of Pharmacy
- Chongqing Medical University
- Chongqing 400016, P. R. China
| | - Jiwei Hu
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
- College of Pharmacy
- Chongqing Medical University
- Chongqing 400016, P. R. China
| | - Rui Wang
- School of Pharmacy & Bioengineering
- Chongqing University of Technology
- Chongqing 400054, P. R. China
| | - Qiang Tang
- Chongqing Key Laboratory of Biochemistry and Molecular Pharmacology
- College of Pharmacy
- Chongqing Medical University
- Chongqing 400016, P. R. China
- The Faculty of Laboratory Medicine
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25
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Adams CS, Weatherly CD, Burke EG, Schomaker JM. The conversion of allenes to strained three-membered heterocycles. Chem Soc Rev 2014; 43:3136-63. [DOI: 10.1039/c3cs60416k] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The addition of heteroatoms to an allenic double bond yields strained heterocycles that serve as scaffolds for further useful transformations.
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Affiliation(s)
- C. S. Adams
- Department of Chemistry
- University of Wisconsin
- Madison, USA
| | | | - E. G. Burke
- Department of Chemistry
- University of Wisconsin
- Madison, USA
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26
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Audran G, Brémond P, Marque SR, Gaudel-Siri A, Siri D, Santelli M. Theoretical modelling of the epoxidation of vinylallenes to give cyclopentenones. Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.09.110] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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27
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Jolit A, Vazquez-Rodriguez S, Yap GPA, Tius MA. Diastereospecific nazarov cyclization of fully substituted dienones: generation of vicinal all-carbon-atom quaternary stereocenters. Angew Chem Int Ed Engl 2013; 52:11102-5. [PMID: 24002922 PMCID: PMC3872134 DOI: 10.1002/anie.201305218] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 07/23/2013] [Indexed: 11/08/2022]
Abstract
No vacancy: Fully substituted dienones that are highly polarized by a vinylogous carbonate group were found to undergo a remarkably rapid and diastereospecific Nazarov cyclization that led to cyclopentenones with vicinal all-carbon-atom quaternary centers (see example; SEM=2-(trimethylsilyl)ethoxymethyl, Tf=trifluoromethanesulfonyl).
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Affiliation(s)
- Anais Jolit
- Chemistry Department, University of Hawaii at Manoa, 2545 The Mall, Honolulu, HI 96822 (USA), Fax: (+) +1-808-956-5908
| | - Saleta Vazquez-Rodriguez
- Chemistry Department, University of Hawaii at Manoa, 2545 The Mall, Honolulu, HI 96822 (USA), Fax: (+) +1-808-956-5908
| | - Glenn P. A. Yap
- Chemistry Department, University of Hawaii at Manoa, 2545 The Mall, Honolulu, HI 96822 (USA), Fax: (+) +1-808-956-5908, Department of Chemistry & Biochemistry, University of Delaware, 236 Brown Laboratory, Newark, DE 19716 (USA)
| | - Marcus A. Tius
- Chemistry Department, University of Hawaii at Manoa, 2545 The Mall, Honolulu, HI 96822 (USA), Fax: (+) +1-808-956-5908, University of Hawaii Cancer Center, 701 Ilalo Street, Honolulu, HI 96813 (USA)
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Jolit A, Vazquez-Rodriguez S, Yap GPA, Tius MA. Diastereospecific Nazarov Cyclization of Fully Substituted Dienones: Generation of Vicinal All-Carbon-Atom Quaternary Stereocenters. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201305218] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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29
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Kwon Y, McDonald R, West FG. Organoaluminum-Mediated Interrupted Nazarov Reaction. Angew Chem Int Ed Engl 2013; 52:8616-9. [DOI: 10.1002/anie.201303996] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2013] [Revised: 06/07/2013] [Indexed: 11/10/2022]
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30
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Kwon Y, McDonald R, West FG. Organoaluminum-Mediated Interrupted Nazarov Reaction. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201303996] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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31
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Wenz DR, Read de Alaniz J. Aza-Piancatelli Rearrangement Initiated by Ring Opening of Donor–Acceptor Cyclopropanes. Org Lett 2013; 15:3250-3. [DOI: 10.1021/ol401248p] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Donald R. Wenz
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
| | - Javier Read de Alaniz
- Department of Chemistry & Biochemistry, University of California, Santa Barbara, California 93106-9510, United States
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32
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Spencer WT, Vaidya T, Frontier AJ. Beyond the Divinyl Ketone: Innovations in the Generation and Nazarov Cyclization of Pentadienyl Cation Intermediates. European J Org Chem 2013; 2013:10.1002/ejoc.201300134. [PMID: 24348092 PMCID: PMC3862358 DOI: 10.1002/ejoc.201300134] [Citation(s) in RCA: 154] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Indexed: 11/09/2022]
Abstract
The requirement for new strategies for synthesizing five-membered carbocycles has driven an expansion in the study of the Nazarov cyclization. This renewed interest in the reaction has led to the discovery of several interesting new methods for generating the pentadienyl cation intermediate central to the cyclization. Methods reviewed include carbon-heteroatom ionization, functionalization of a double bond, nucleophilic addition, or electrocyclic ring opening. Additional variations employ unconventional substrates to produce novel pentacycles, such as the iso- and imino-Nazarov. Herein, we provide an overview of these unconventional, yet highly useful versions of the Nazarov cyclization.
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Affiliation(s)
- William T. Spencer
- Department of Chemistry, University of Rochester, RC Box 270216, Rochester, NY 14627
| | - Tulaza Vaidya
- Department of Chemistry and Chemical Biology, Cornell University Baker Laboratory Ithaca, NY 14853
| | - Alison J. Frontier
- Department of Chemistry, University of Rochester, RC Box 270216, Rochester, NY 14627
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33
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Lebœuf D, Wright CM, Frontier AJ. Reagent Control of [1,2]-Wagner-Meerwein Shift Chemoselectivity Following the Nazarov Cyclization: Application to the Total Synthesis of Enokipodin B. Chemistry 2013; 19:4835-41. [PMID: 23436444 DOI: 10.1002/chem.201203395] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2012] [Revised: 11/26/2012] [Indexed: 02/05/2023]
Affiliation(s)
- David Lebœuf
- Department of Chemistry, University of Rochester, Rochester, NY 14627, USA
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34
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Ma ZX, He S, Song W, Hsung RP. α-Aryl-substituted allenamides in an imino-Nazarov cyclization cascade catalyzed by Au(I). Org Lett 2012; 14:5736-9. [PMID: 23121692 DOI: 10.1021/ol302743k] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
An imino-Nazarov cyclization using α-aryl-substituted allenamides is described. This gold(I)-catalyzed cascade is efficient and regioselective in constructing a diverse array of synthetically useful aromatic-ring fused cyclopentenamides. The success in this transformation represents a solution to the challenge in establishing an imino-Nazarov cyclization process.
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Affiliation(s)
- Zhi-Xiong Ma
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin, Madison, Wisconsin 53705, USA
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35
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Spencer WT, Frontier AJ. Cycloaromatization protocol for synthesis of polysubstituted phenol derivatives: method development and mechanistic studies. J Org Chem 2012; 77:7730-6. [PMID: 22891882 DOI: 10.1021/jo3010952] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The scope of the cycloaromatization of propargylic ethers was explored using operationally simple air- and moisture-insensitive conditions. Highly substituted phenol derivatives were obtained in high yields. Mechanistic experiments indicate that the reaction occurs by an electrocyclization followed by 1,3-proton transfer.
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Affiliation(s)
- William T Spencer
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
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36
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Lebœuf D, Gandon V, Ciesielski J, Frontier AJ. Experimental and theoretical studies on the Nazarov cyclization/Wagner-Meerwein rearrangement sequence. J Am Chem Soc 2012; 134:6296-308. [PMID: 22471833 PMCID: PMC3382077 DOI: 10.1021/ja211970p] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Highly functionalized cyclopentenones can be generated by a chemoselective copper(II)-mediated Nazarov/Wagner-Meerwein rearrangement sequence of divinyl ketones. A detailed investigation of this sequence is described including a study of substrate scope and limitations. After the initial 4π electrocyclization, this reaction proceeds via two different sequential [1,2]-shifts, with selectivity that depends upon either migratory ability or the steric bulkiness of the substituents at C1 and C5. This methodology allows the creation of vicinal stereogenic centers, including adjacent quaternary centers. This sequence can also be achieved by using a catalytic amount of copper(II) in combination with NaBAr(4)(f), a weak Lewis acid. During the study of the scope of the reaction, a partial or complete E/Z isomerization of the enone moiety was observed in some cases prior to the cyclization, which resulted in a mixture of diastereomeric products. Use of a Cu(II)-bisoxazoline complex prevented the isomerization, allowing high diastereoselectivity to be obtained in all substrate types. In addition, the reaction sequence was studied by DFT computations at the UB3LYP/6-31G(d,p) level, which are consistent with the proposed sequences observed, including E/Z isomerizations and chemoselective Wagner-Meerwein shifts.
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Affiliation(s)
- David Lebœuf
- Department of Chemistry, University of Rochester, Rochester, NY 14627
| | - Vincent Gandon
- ICMMO, UMR CNRS 8182, Université Paris-Sud 11, 91405 Orsay cedex, France
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37
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Malona JA, Cariou K, Spencer WT, Frontier AJ. Total synthesis of (±)-rocaglamide via oxidation-initiated Nazarov cyclization. J Org Chem 2012; 77:1891-908. [PMID: 22283818 DOI: 10.1021/jo202366c] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
This article describes the evolution of a Nazarov cyclization-based synthetic strategy targeting the anticancer, antiinflammatory, and insecticidal natural product (±)-rocaglamide. Initial pursuit of a polarized heteroaromatic Nazarov cyclization to construct the congested cyclopentane core revealed an unanticipated electronic bias in the pentadienyl cation. This reactivity was harnessed in a successful second-generation approach using an oxidation-initiated Nazarov cyclization of a heteroaryl alkoxyallene. Full details of these two approaches are given, as well as the characterization of undesired reaction pathways available to the Nazarov cyclization product. A sequence of experiments that led to an understanding of the unexpected reactivity of this key intermediate is described, which culminated in the successful total synthesis of (+)-rocaglamide.
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Affiliation(s)
- John A Malona
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
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38
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Allenes in Catalytic Asymmetric Synthesis and Natural Product Syntheses. Angew Chem Int Ed Engl 2012; 51:3074-112. [DOI: 10.1002/anie.201101460] [Citation(s) in RCA: 758] [Impact Index Per Article: 63.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2011] [Indexed: 02/06/2023]
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39
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Yu S, Ma S. Allene in katalytischer asymmetrischer Synthese und Naturstoffsynthese. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201101460] [Citation(s) in RCA: 254] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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40
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Abstract
A reaction sequence involving the 1,6-conjugate addition of a nucleophile to a dienyl diketone followed by Nazarov cyclization is described. Several nucleophiles are identified as competent initiators for the sequence. A different reaction outcome is observed when catalytic amounts of nucleophile are employed, involving elimination of the nucleophile after the electrocyclization.
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Affiliation(s)
- Joshua L Brooks
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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41
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Wu YK, McDonald R, West FG. Homologous Mukaiyama Reactions via Trapping of the Nazarov Intermediate with Silyloxyalkenes. Org Lett 2011; 13:3584-7. [DOI: 10.1021/ol201125h] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yen-Ku Wu
- Department of Chemistry, University of Alberta, E3-43 Gunning-Lemieux Chemistry Centre, Edmonton, AB T6G 2G2, Canada
| | - Robert McDonald
- Department of Chemistry, University of Alberta, E3-43 Gunning-Lemieux Chemistry Centre, Edmonton, AB T6G 2G2, Canada
| | - F. G. West
- Department of Chemistry, University of Alberta, E3-43 Gunning-Lemieux Chemistry Centre, Edmonton, AB T6G 2G2, Canada
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42
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Li WDZ, Duo WG, Zhuang CH. Concise Total Synthesis of (±)-Cephalotaxine via a Transannulation Strategy: Development of a Facile Reductive oxy-Nazarov Cyclization. Org Lett 2011; 13:3538-41. [DOI: 10.1021/ol201390r] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Wei-Dong Z. Li
- State Key Laboratory of Elemento-organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Wei-Guo Duo
- State Key Laboratory of Elemento-organic Chemistry, Nankai University, Tianjin 300071, P. R. China
| | - Cheng-Han Zhuang
- State Key Laboratory of Elemento-organic Chemistry, Nankai University, Tianjin 300071, P. R. China
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