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Rodrigues Jr. MT, de Oliveira ASB, Gomes RC, Hirata AS, Zeoly LA, Santos H, Arantes J, Reis-Silva CSM, Machado-Neto JA, Costa-Lotufo LV, Coelho F. Bismuth(III) triflate: an economical and environmentally friendly catalyst for the Nazarov reaction. Beilstein J Org Chem 2024; 20:1167-1178. [PMID: 38887581 PMCID: PMC11181232 DOI: 10.3762/bjoc.20.99] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 05/02/2024] [Indexed: 06/20/2024] Open
Abstract
We describe the use of bismuth(III) triflate as an efficient and environmentally friendly catalyst for the Nazarov reaction of aryl vinyl ketones, leading to the synthesis of 3-aryl-2-ethoxycarbonyl-1-indanones and 3-aryl-1-indanones. By changing the temperature and reaction time, it was possible to modulate the reactivity, allowing the synthesis of two distinct product classes (3-aryl-2-ethoxycarbonyl-1-indanones and 3-aryl-1-indanones) in good to excellent yield. The reaction did not require additives and was insensitive to both air and moisture. Preliminary biological evaluation of some indanones showed a promising profile against some human cancer line cells.
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Affiliation(s)
| | | | - Ralph C Gomes
- Institute of Chemistry, Universidade Estadual de Campinas, PO Box 6154, 13083-970 Campinas, São Paulo, Brazil
| | - Amanda Soares Hirata
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil
| | - Lucas A Zeoly
- Institute of Chemistry, Universidade Estadual de Campinas, PO Box 6154, 13083-970 Campinas, São Paulo, Brazil
| | - Hugo Santos
- Institute of Chemistry, Universidade Estadual de Campinas, PO Box 6154, 13083-970 Campinas, São Paulo, Brazil
| | - João Arantes
- Institute of Chemistry, Universidade Estadual de Campinas, PO Box 6154, 13083-970 Campinas, São Paulo, Brazil
| | | | - João Agostinho Machado-Neto
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil
| | - Leticia Veras Costa-Lotufo
- Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, 05508-000 São Paulo, Brazil
| | - Fernando Coelho
- Institute of Chemistry, Universidade Estadual de Campinas, PO Box 6154, 13083-970 Campinas, São Paulo, Brazil
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2
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Unexpected Decarbonylation of Acylethynylpyrroles under the Action of Cyanomethyl Carbanion: A Robust Access to Ethynylpyrroles. Molecules 2023; 28:molecules28031389. [PMID: 36771055 PMCID: PMC9919934 DOI: 10.3390/molecules28031389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/25/2023] [Accepted: 01/26/2023] [Indexed: 02/04/2023] Open
Abstract
It has been found that the addition of CH2CN- anion to the carbonyl group of acylethynylpyrroles, generated from acetonitrile and t-BuOK, results in the formation of acetylenic alcohols, which undergo unexpectedly easy (room temperature) decomposition to ethynylpyrroles and cyanomethylphenylketones (retro-Favorsky reaction). This finding allows a robust synthesis of ethynylpyrroles in up to 95% yields to be developed. Since acylethynylpyrroles became available, the strategy thus found makes ethynylpyrroles more accessible than earlier. The quantum-chemical calculations (B2PLYP/6-311G**//B3LYP/6-311G**+C-PCM/acetonitrile) confirm the thermodynamic preference of the decomposition of the intermediate acetylenic alcohols to free ethynylpyrroles rather than their potassium derivatives.
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Danelzik T, Joseph S, Mück-Lichtenfeld C, Daniliuc CG, García Mancheño O. Benzotriazolium Salts: Emergent Readily Accessible Bench-Stable Lewis Acid Catalysts. Org Lett 2022; 24:6105-6110. [PMID: 35972895 PMCID: PMC9434991 DOI: 10.1021/acs.orglett.2c01697] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
In this work, benzotriazolium salts have been introduced
as efficient,
readily accessible, bench-stable Lewis acid catalysts. Though these
sorts of N-heterocyclic compounds have found wide applications as
ionic liquids or electrolytes, their Lewis acid catalytic activity
remained unexplored. Herein, their potential as Lewis acid catalysts
was demonstrated in two prototypical allylic and Nazarov cyclization
reactions, showing a matching reactivity and allowing low catalytic
loadings (down to 0.5 mol %).
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Affiliation(s)
- Tobias Danelzik
- Organic Chemistry Institute, Westfälische Wilhelms University Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Sumi Joseph
- Organic Chemistry Institute, Westfälische Wilhelms University Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Christian Mück-Lichtenfeld
- Organic Chemistry Institute, Westfälische Wilhelms University Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Constantin G Daniliuc
- Organic Chemistry Institute, Westfälische Wilhelms University Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Olga García Mancheño
- Organic Chemistry Institute, Westfälische Wilhelms University Münster, Corrensstraße 36, 48149 Münster, Germany
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Yadykov AV, Yaminova LV, Krayushkin MM, Shirinian VZ. Cyclization of Polarized Divinyl Ketones under Aqueous and Ambient Conditions. Adv Synth Catal 2021. [DOI: 10.1002/adsc.202000956] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Anton V. Yadykov
- N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences 47 Leninsky prosp. 119991 Moscow Russian Federation
| | - Liana V. Yaminova
- N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences 47 Leninsky prosp. 119991 Moscow Russian Federation
| | - Mikhail M. Krayushkin
- N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences 47 Leninsky prosp. 119991 Moscow Russian Federation
| | - Valerii Z. Shirinian
- N. D. Zelinsky Institute of Organic Chemistry Russian Academy of Sciences 47 Leninsky prosp. 119991 Moscow Russian Federation
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5
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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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6
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Sadanandan S, Gupta DK. Changing stereoselectivity and regioselectivity in copper( i)-catalyzed 5- exo cyclization by chelation and rigidity in aminoalkyl radicals: synthesis towards diverse bioactive N-heterocycles. NEW J CHEM 2020. [DOI: 10.1039/c9nj05166j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Chelation, rigidity and carbon-radical positions in aminoalkyl precursors disturb the usual 2,4-trans diastereoselectivity and 5-exo mode in Cu(i)-catalyzed ATRC.
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7
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Zhang X, Zhang C, Wang X, Liang G. Mild Friedel-Crafts Reactions Enable a Robust Synthesis of Roseophilin. Org Lett 2019; 21:3357-3360. [PMID: 31008613 DOI: 10.1021/acs.orglett.9b01100] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
An 11-step total synthesis of either enantiomer of roseophilin has been developed. The chemistry features effective production of a challenging carbocation on a macrocyclic segment 25 and a highly efficient intermolecular Friedel-Crafts alkylation reaction to integrate a complex furan-pyrrole unit 5 regioselectively with this carbocation under very mild reaction conditions.
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Affiliation(s)
- Xiao Zhang
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Cuifang Zhang
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Xiaobin Wang
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
| | - Guangxin Liang
- State Key Laboratory of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China
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8
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Zheng K, Hong R. Stereoconfining macrocyclizations in the total synthesis of natural products. Nat Prod Rep 2019; 36:1546-1575. [DOI: 10.1039/c8np00094h] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
This review covers selected examples of point chirality-forming macrocyclizations in natural product total synthesis in the past three decades.
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Affiliation(s)
- Kuan Zheng
- Key Laboratory of Synthetic Chemistry of Natural Substances
- Center for Excellence in Molecular Synthesis
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
| | - Ran Hong
- Key Laboratory of Synthetic Chemistry of Natural Substances
- Center for Excellence in Molecular Synthesis
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
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9
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Ashley WL, Timpy EL, Coombs TC. Flow Photo-Nazarov Reactions of 2-Furyl Vinyl Ketones: Cyclizing a Class of Traditionally Unreactive Heteroaromatic Enones. J Org Chem 2018; 83:2516-2529. [PMID: 29400058 DOI: 10.1021/acs.joc.7b03171] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Nazarov reactions of 2-furyl vinyl ketones and related heteroaromatic enones, to produce furan-fused cyclopentanones using a flow photochemical approach, are described. Compounds possessing this connectivity between heterocycle and ketone (2-furyl, 2-benzofuryl, 2-thiophene-yl, and 2-benzothiophene-yl) have traditionally proven difficult or impossible to cyclize with typical Brønsted and Lewis acid mediated methods. Using mild flow photochemistry conditions and acetic acid (AcOH) or hexafluoroisopropanol (HFIP) as solvent, these compounds were found to cyclize in 45-97% yields, with typical UV exposure times of 3.4-6.8 min. In all cases, 2-furyl and 2-thiophene-yl enones cyclized, whereas 2-benzofuryl and 2-benzothiophene-yl enones exhibited divergent properties with reactivity patterns tied to the identity of the vinyl group. This report discloses the first photo-Nazarov reactions of tetrahydropyridine-substituted 2-furyl ketones, providing a direct approach to the corresponding fused heterocyclic motifs built around a central cyclopentanone. These motifs constitute the core structures of biologically active natural products, including the marine alkaloid nakadomarin A.
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Affiliation(s)
- William L Ashley
- Department of Chemistry and Biochemistry, University of North Carolina Wilmington , Dobo Hall, Wilmington, North Carolina 28403, United States
| | - Evan L Timpy
- Department of Chemistry and Biochemistry, University of North Carolina Wilmington , Dobo Hall, Wilmington, North Carolina 28403, United States
| | - Thomas C Coombs
- Department of Chemistry and Biochemistry, University of North Carolina Wilmington , Dobo Hall, Wilmington, North Carolina 28403, United States
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10
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Zhang S, Lindsey JS. Construction of the Bacteriochlorin Macrocycle with Concomitant Nazarov Cyclization To Form the Annulated Isocyclic Ring: Analogues of Bacteriochlorophyll a. J Org Chem 2017; 82:2489-2504. [DOI: 10.1021/acs.joc.6b02878] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shaofei Zhang
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Jonathan S. Lindsey
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
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11
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Marin L, Gandon V, Schulz E, Lebœuf D. One-Pot Assembly of Highly Functionalized Cyclopenta[b]pyrrolesviaa Calcium(II)- and Copper(II)-Catalyzed Reaction Sequence. Adv Synth Catal 2017. [DOI: 10.1002/adsc.201601301] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Lucile Marin
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182; Université Paris-Sud, Université Paris-Saclay; Bâtiment 420 91405 Orsay cedex France
| | - Vincent Gandon
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182; Université Paris-Sud, Université Paris-Saclay; Bâtiment 420 91405 Orsay cedex France
| | - Emmanuelle Schulz
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182; Université Paris-Sud, Université Paris-Saclay; Bâtiment 420 91405 Orsay cedex France
| | - David Lebœuf
- Institut de Chimie Moléculaire et des Matériaux d'Orsay, CNRS UMR 8182; Université Paris-Sud, Université Paris-Saclay; Bâtiment 420 91405 Orsay cedex France
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12
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Hayashi T, Ohmori K, Suzuki K. Synthetic Study on Carthamin. 2. Stereoselective Approach to C-Glycosyl Quinochalcone via Desymmetrization. Org Lett 2017; 19:866-869. [DOI: 10.1021/acs.orglett.6b03899] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Taiki Hayashi
- Department of Chemistry, Tokyo Institute of Technology, O-okayama,
Meguro-ku, Tokyo 152-8551, Japan
| | - Ken Ohmori
- Department of Chemistry, Tokyo Institute of Technology, O-okayama,
Meguro-ku, Tokyo 152-8551, Japan
| | - Keisuke Suzuki
- Department of Chemistry, Tokyo Institute of Technology, O-okayama,
Meguro-ku, Tokyo 152-8551, Japan
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13
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Grenet E, Martinez J, Salom-Roig XJ. Torquoselective Nazarov Cyclization Mediated by a Chiral Sulfoxide: First Enantioselective Synthesis of two Known Anticancer Agents. ASIAN J ORG CHEM 2016. [DOI: 10.1002/ajoc.201600471] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Erwann Grenet
- Institut de Biomolécules Max Mousseron (IBMM); UMR 5247; Université de Montpellier, CNRS, ENSCM; Place Eugène Bataillon 34095 Montpellier France
| | - Jean Martinez
- Institut de Biomolécules Max Mousseron (IBMM); UMR 5247; Université de Montpellier, CNRS, ENSCM; Place Eugène Bataillon 34095 Montpellier France
| | - Xavier J. Salom-Roig
- Institut de Biomolécules Max Mousseron (IBMM); UMR 5247; Université de Montpellier, CNRS, ENSCM; Place Eugène Bataillon 34095 Montpellier France
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Hu DX, Withall DM, Challis GL, Thomson RJ. Structure, Chemical Synthesis, and Biosynthesis of Prodiginine Natural Products. Chem Rev 2016; 116:7818-53. [PMID: 27314508 PMCID: PMC5555159 DOI: 10.1021/acs.chemrev.6b00024] [Citation(s) in RCA: 108] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The prodiginine family of bacterial alkaloids is a diverse set of heterocyclic natural products that have likely been known to man since antiquity. In more recent times, these alkaloids have been discovered to span a wide range of chemical structures that possess a number of interesting biological activities. This review provides a comprehensive overview of research undertaken toward the isolation and structural elucidation of the prodiginine family of natural products. Additionally, research toward chemical synthesis of the prodiginine alkaloids over the last several decades is extensively reviewed. Finally, the current, evidence-based understanding of the various biosynthetic pathways employed by bacteria to produce prodiginine alkaloids is summarized.
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Affiliation(s)
- Dennis X. Hu
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - David M. Withall
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Gregory L. Challis
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, United Kingdom
| | - Regan J. Thomson
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
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15
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16
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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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17
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Wu K, Wu P, Chen J, Sun C, Yu Z. Brønsted Acid-Promoted Cascade Alkylation/Cyclization of Pyrroles withN,N-Dimethylaminomethyleneglutaconic Acid Dinitrile: A Concise Route to Cyclopenta[b]pyrroles. Adv Synth Catal 2015. [DOI: 10.1002/adsc.201500546] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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18
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Yang X, Wu K, Wu P, Chen J, Sun C, Yu Z. Brønsted Acid-Mediated Annulation of α-Oxo Ketene Dithioacetals with Pyrroles: Efficient Synthesis of Structurally Diverse Cyclopenta[b]pyrroles. Chemistry 2015; 21:9323-7. [DOI: 10.1002/chem.201501022] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Indexed: 11/06/2022]
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19
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Petrović M, Scarpi D, Fiser B, Gómez-Bengoa E, Occhiato EG. Annulated N-Heterocycles by Tandem Gold(I)-Catalyzed [3,3]-Rearrangement/Nazarov Reaction of Propargylic Ester Derivatives: an Experimental and Computational Study. European J Org Chem 2015. [DOI: 10.1002/ejoc.201500462] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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20
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Ronson TO, Taylor RJ, Fairlamb IJ. Palladium-catalysed macrocyclisations in the total synthesis of natural products. Tetrahedron 2015. [DOI: 10.1016/j.tet.2014.11.009] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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21
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Nisha N, Kumar K, Kumar V. Prodigiosin alkaloids: recent advancements in total synthesis and their biological potential. RSC Adv 2015. [DOI: 10.1039/c4ra10296g] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The present review article is focused on the medicinal potential and total synthesis of prodigiosins witnessed in the last decade. The aim will be to provide an inspiration to the marvels and pit falls of constructing the polypyrrole heterocycles with in the complex systems.
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Affiliation(s)
- Nisha Nisha
- Department of Chemistry
- Guru Nanak Dev University
- Amritsar-143005
- India
| | - Kewal Kumar
- Department of Chemistry
- Guru Nanak Dev University
- Amritsar-143005
- India
| | - Vipan Kumar
- Department of Chemistry
- Guru Nanak Dev University
- Amritsar-143005
- India
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22
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Xu Z, Ren H, Wang L, Tang Y. Efficient catalytic enantioselective Nazarov cyclizations of divinyl ketoesters. Org Chem Front 2015. [DOI: 10.1039/c5qo00099h] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An efficient catalytic enantioselective Nazarov cyclization of divinyl ketoesters is developed using a BOX/Cu(ii) catalyst, affording various optically active cyclopent-2-enone esters.
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Affiliation(s)
- Zhou Xu
- State Key Laboratory of Organometallic Chemistry
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- China
| | - Hai Ren
- State Key Laboratory of Organometallic Chemistry
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- China
| | - Lijia Wang
- State Key Laboratory of Organometallic Chemistry
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- China
| | - Yong Tang
- State Key Laboratory of Organometallic Chemistry
- Shanghai Institute of Organic Chemistry
- Chinese Academy of Sciences
- Shanghai 200032
- China
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23
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Sobenina LN, Tomilin DN, Trofimov BA. C-Ethynylpyrroles: synthesis and reactivity. RUSSIAN CHEMICAL REVIEWS 2014. [DOI: 10.1070/rc2014v083n06abeh004418] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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24
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P. Sibi M, L. Dunkle K, Rane D. Regio- and Enantioselective Nitrone Cycloaddition to Alkynones for the Synthesis of Δ4-Isoxazolines. HETEROCYCLES 2014. [DOI: 10.3987/com-13-s(s)118] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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25
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Madabhushi S, Godala KR, Jillella R, Mallu KKR, Chinthala N. A new multicomponent approach to highly functionalized 2,3-dihydroisoxazoles. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2013.11.087] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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26
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Li E, Li C, Wang J, Wang J, Dong L, Guo X, Song C, Chang J. Lewis acid-catalyzed tandem acylation–Nazarov cyclization for the syntheses of fused cyclopentenones. Tetrahedron 2014. [DOI: 10.1016/j.tet.2013.12.025] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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27
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Frederich JH, Harran PG. Modular access to complex prodiginines: total synthesis of (+)-roseophilin via its 2-azafulvene prototropisomer. J Am Chem Soc 2013; 135:3788-91. [PMID: 23452332 PMCID: PMC3675760 DOI: 10.1021/ja400473v] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ansa-bridged prodiginines are bioactive pigments produced by bacteria. Certain of these structures are reported to be antagonists of protein-protein interactions involved in apoptosis. We describe a new entry to alkaloids of this type, demonstrated with a concise asymmetric synthesis of (+)-roseophilin (3). Our route constructs the pyrrolophane motif via phosphoryl transfer-terminated macroaldolization and passes through a previously unexplored prototropic form of the natural product.
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Affiliation(s)
- James H. Frederich
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095-1569
| | - Patrick G. Harran
- Department of Chemistry and Biochemistry, University of California, Los Angeles, 607 Charles E. Young Drive East, Los Angeles, California 90095-1569
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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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29
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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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30
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Shimada N, Stewart C, Bow WF, Jolit A, Wong K, Zhou Z, Tius MA. Neutral Nazarov-type cyclization catalyzed by palladium(0). Angew Chem Int Ed Engl 2012; 51:5727-9. [PMID: 22539448 DOI: 10.1002/anie.201201724] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2012] [Indexed: 11/11/2022]
Affiliation(s)
- Naoyuki Shimada
- Chemistry Department, University of Hawaii at Manoa, 2545 The Mall, Honolulu, HI 96822, USA
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31
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Shimada N, Stewart C, Bow WF, Jolit A, Wong K, Zhou Z, Tius MA. Neutral Nazarov-Type Cyclization Catalyzed by Palladium(0). Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201201724] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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32
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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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33
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Kerr DJ, Flynn BL. A New Approach to Highly Substituted Cyclopentanoids from a Concise Formal Synthesis of (+)-Roseophilin. Org Lett 2012; 14:1740-3. [DOI: 10.1021/ol300332b] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel J. Kerr
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
| | - Bernard L. Flynn
- Medicinal Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, 381 Royal Parade, Parkville, Victoria 3052, Australia
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34
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Gulder T, Baran PS. Strained cyclophane natural products: Macrocyclization at its limits. Nat Prod Rep 2012; 29:899-934. [DOI: 10.1039/c2np20034a] [Citation(s) in RCA: 102] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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35
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Song C, Liu H, Hong M, Liu Y, Jia F, Sun L, Pan Z, Chang J. Convergent Formal Synthesis of (±)-Roseophilin. J Org Chem 2011; 77:704-6. [DOI: 10.1021/jo201949x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Chuanjun Song
- Department of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan Province 450001, PR China
| | - Hui Liu
- Department of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan Province 450001, PR China
| | - Meiling Hong
- Department of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan Province 450001, PR China
| | - Yuanyuan Liu
- Department of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan Province 450001, PR China
| | - Feifei Jia
- Department of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan Province 450001, PR China
| | - Li Sun
- Department of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan Province 450001, PR China
| | - Zhenliang Pan
- Department of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan Province 450001, PR China
| | - Junbiao Chang
- Department of Chemistry, Zhengzhou University, 100 Science Avenue, Zhengzhou, Henan Province 450001, PR China
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36
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Lebœuf D, Huang J, Gandon V, Frontier AJ. Using Nazarov electrocyclization to stage chemoselective [1,2]-migrations: stereoselective synthesis of functionalized cyclopentenones. Angew Chem Int Ed Engl 2011; 50:10981-5. [PMID: 21953873 DOI: 10.1002/anie.201104870] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 08/17/2011] [Indexed: 11/08/2022]
Affiliation(s)
- David Lebœuf
- Department of Chemistry, University of Rochester, Rochester, NY 14627, USA
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37
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Zhang L, Xu X, Xia W, Liu Q. Bicyclization of Isocyanides: A Synthetic Strategy for Fused Pyrroles. Adv Synth Catal 2011. [DOI: 10.1002/adsc.201100501] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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38
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Lebœuf D, Huang J, Gandon V, Frontier AJ. Using Nazarov Electrocyclization to Stage Chemoselective [1,2]-Migrations: Stereoselective Synthesis of Functionalized Cyclopentenones. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201104870] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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39
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Subramanium SS, Handa S, Miranda AJ, Slaughter LM. Simple Silver Salts and Palladium Bis(N-heterocyclic carbene) Complexes As Complementary Catalysts for the Nazarov Cyclization. ACS Catal 2011. [DOI: 10.1021/cs200449g] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sri S. Subramanium
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma, 74078
| | - Sachin Handa
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma, 74078
| | - Anthea J. Miranda
- Department of Chemistry, Oklahoma State University, Stillwater, Oklahoma, 74078
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40
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41
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42
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Huang J, Lebœuf D, Frontier AJ. Understanding the fate of the oxyallyl cation following Nazarov electrocyclization: sequential Wagner-Meerwein migrations and the synthesis of spirocyclic cyclopentenones. J Am Chem Soc 2011; 133:6307-17. [PMID: 21466152 DOI: 10.1021/ja111504w] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A general reaction sequence is described that involves Nazarov cyclization followed by two sequential Wagner-Meerwein migrations, to afford spirocyclic compounds from divinyl ketones in the presence of 1 equiv of copper(II) complexes. A detailed investigation of this sequence is described including a study of substrate scope and limitations. It was found that after 4π electrocyclization, two different pathways are available to the oxyallyl cation intermediate: elimination of a proton can give the usual Nazarov cycloadduct, or ring contraction can give an alternative tertiary carbocation. After ring contraction, either [1,2]-hydride or carbon migration can occur, depending upon the substitution pattern of the substrate, to furnish spirocyclic products. The rearrangement pathway is favored over the elimination pathway when catalyst loading is high and the copper(II) counterion is noncoordinating. Several ligands were found to be effective for the reaction. Thus, the reaction sequence can be controlled by judicious choice of reaction conditions to allow selective generation of richly functionalized spirocycles. The three steps of the sequence are stereospecific: electrocyclization followed by two [1,2]-suprafacial Wagner-Meerwein shifts, the ring contraction and then a hydride, alkenyl, or aryl shift. The method allows stereospecific installation of adjacent stereocenters or adjacent quaternary centers arrayed around a cyclopentenone ring.
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Affiliation(s)
- Jie Huang
- Department of Chemistry, University of Rochester, Rochester, New York 14627, USA
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43
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Vaidya T, Manbeck GF, Chen S, Frontier AJ, Eisenberg R. Divergent reaction pathways of a cationic intermediate: rearrangement and cyclization of 2-substituted furyl and benzofuryl enones catalyzed by iridium(III). J Am Chem Soc 2011; 133:3300-3. [PMID: 21322633 DOI: 10.1021/ja111317q] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In contrast to 2-substituted pyrrole enones, furyl and benzofuryl enones do not undergo the Nazarov electrocyclization. Instead, these furyl and benzofuryl enones exhibit unusual rearrangement sequences in the presence of catalytic amounts of [IrBr(CO)(DIM)((R)-(+)-BINAP)](SbF(6))(2) (1; DIM = diethylisopropylidene malonate) and AgSbF(6) (1:1). A 1,2-H shift followed by intramolecular Friedel-Crafts alkylation leads to synthetically valuable cyclohexanones with furanylic quaternary centers. The electrophilicity of 1 is essential for this rearrangement.
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Affiliation(s)
- Tulaza Vaidya
- Department of Chemistry, University of Rochester, Rochester, New York 14627, United States
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44
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Five-Membered Ring Systems. ACTA ACUST UNITED AC 2011. [DOI: 10.1016/s0959-6380(11)22006-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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45
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Marx VM, LeFort FM, Burnell DJ. Trapping the Oxyallyl Cation Intermediate Derived from the Nazarov Cyclization of Allenyl Vinyl Ketones with Nitrogen Heterocycles. Adv Synth Catal 2010. [DOI: 10.1002/adsc.201000722] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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46
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Dobish MC, Johnston JN. Chiral Brønsted base-promoted nitroalkane alkylation: enantioselective synthesis of sec-alkyl-3-substituted indoles. Org Lett 2010; 12:5744-7. [PMID: 21090654 DOI: 10.1021/ol1025712] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A Brønsted base-catalyzed reaction of nitroalkanes with alkyl electrophiles provides indole heterocycles substituted at C3 bearing a sec-alkyl group with good enantioselectivity (up to 90% ee). Denitration by hydrogenolysis provides a product with equally high ee. An indolenine intermediate is implicated in the addition step, and surprisingly, water cosolvent was found to have a beneficial effect in this step, leading to a one-pot protocol for elimination/enantioselective addition using PBAM, a bis(amidine) chiral nonracemic base.
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Affiliation(s)
- Mark C Dobish
- Department of Chemistry & Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235-1822, USA
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47
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Basak AK, Shimada N, Bow WF, Vicic DA, Tius MA. An organocatalytic asymmetric Nazarov cyclization. J Am Chem Soc 2010; 132:8266-7. [PMID: 20507121 DOI: 10.1021/ja103028r] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An organocatalytic asymmetric Nazarov cyclization of diketoesters that proceeds by means of a dual activation mechanism has been developed. Screening of a number of catalysts led to a new thiourea that incorporates a primary amino group. The method gives rise to cyclic products with two adjacent quaternary asymmetric carbon atoms, one of which is an all-carbon stereocenter, with complete or nearly complete diastereoselectivity and in high or very high enantiomeric excess. A brief and very convenient synthesis of the acyclic diketoester starting materials through nucleophilic addition to a ketene is also described.
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Affiliation(s)
- Ashok K Basak
- Department of Chemistry, 2545 The Mall, University of Hawaii, Honolulu, Hawaii 96822, USA
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48
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Yu X, Du B, Wang K, Zhang J. Highly substituted 2,3-dihydroisoxazoles by Et(3)N-catalyzed tandem reaction of electron-deficient 1,3-conjugated enynes with hydroxylamines. Org Lett 2010; 12:1876-9. [PMID: 20334427 DOI: 10.1021/ol100490y] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
An Et(3)N-catalyzed tandem reaction of electron-deficient 1,3-conjugated enynes with hydroxylamines was developed which provided rapid, metal-free, and regioselective access to highly substituted multifunctionalized 2,3-dihydroisoxazoles under mild conditions. The reactions of 3-(2-arylethynyl)-4H-chromen-4-ones with hydroxylamines afford beta-amino enones under the same reaction conditions.
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Affiliation(s)
- Xiuzhao Yu
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes, Department of Chemistry, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, PR China
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49
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Cao P, Deng C, Zhou YY, Sun XL, Zheng JC, Xie Z, Tang Y. Asymmetric Nazarov Reaction Catalyzed by Chiral Tris(oxazoline)/Copper(II). Angew Chem Int Ed Engl 2010. [DOI: 10.1002/ange.200907266] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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50
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Cao P, Deng C, Zhou YY, Sun XL, Zheng JC, Xie Z, Tang Y. Asymmetric Nazarov Reaction Catalyzed by Chiral Tris(oxazoline)/Copper(II). Angew Chem Int Ed Engl 2010; 49:4463-6. [DOI: 10.1002/anie.200907266] [Citation(s) in RCA: 118] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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