1
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Hu L, Rawal VH. Total Synthesis of the Chlorinated Pentacyclic Indole Alkaloid (+)-Ambiguine G. J Am Chem Soc 2021; 143:10872-10875. [PMID: 34279940 PMCID: PMC8509925 DOI: 10.1021/jacs.1c05762] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Indexed: 11/30/2022]
Abstract
Reported herein is the total synthesis of (+)-ambiguine G, the first member of the chlorinated pentacyclic ambiguines to yield to chemical synthesis. The synthesis is accomplished through a convergent strategy that proceeds in 10 steps from (S)-carvone oxide. Pivotal to the concise route is the successful realization of a [4+3] cycloaddition that conjoins two easily synthesized components of the carbon framework of the natural product. Also featured in the synthesis is the efficient, diastereoselective construction of a key vinylated chloro ketone and the unprecedented, one-pot reduction-elimination-oxidation sequence that transforms an enone to an advanced hydroxylated-diene intermediate.
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Affiliation(s)
- Lingbowei Hu
- Department of Chemistry, University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United
States
| | - Viresh H. Rawal
- Department of Chemistry, University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United
States
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2
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Lam H, Lautens M, Abel-Snape X, Köllen MF. Recent Advances in Transition-Metal-Free (4+3)-Annulations. SYNTHESIS-STUTTGART 2021. [DOI: 10.1055/s-0040-1706023] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Abstract(4+3)-Annulations are incredibly versatile reactions which combine a 4-atom synthon and a 3-atom synthon to form both 7-membered carbocycles as well as heterocycles. We have previously reviewed transition-metal-catalyzed (4+3)-annulations. In this review, we will cover examples involving bases, NHCs, phosphines, Lewis and Brønsted acids as well as some rare examples of boronic acid catalysis and photocatalysis. In analogy to our previous review, we exclude annulations involving cyclic dienes like furan, pyrrole, cyclohexadiene or cyclopentadiene, as Chiu, Harmata, Fernándes and others have recently published reviews encompassing such substrates. We will however discuss the recent additions (2010–2020) to the literature on (4+3)-annulations involving other types of 4-atom-synthons.1 Introduction2 Bases3 Annulations Using N-Heterocyclic Carbenes3.1 N-Heterocyclic Carbenes (NHCs)3.2 N-Heterocyclic Carbenes and Base Dual-Activation4 Phosphines5 Acids5.1 Lewis Acids5.2 Brønsted Acids6 Boronic Acid Catalysis and Photocatalysis7 Conclusion
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Affiliation(s)
- Heather Lam
- Davenport Research Laboratories, Department of Chemistry, University of Toronto
| | - Mark Lautens
- Davenport Research Laboratories, Department of Chemistry, University of Toronto
| | - Xavier Abel-Snape
- Davenport Research Laboratories, Department of Chemistry, University of Toronto
| | - Martin F. Köllen
- Ludwig-Maximilians-Universität München, Department Chemie und Biochemie
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3
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Chen L, Zou YX, Zheng SL, Liu XY, Yang HL, Zhang J, Zeng Y, Duan L, Wen Z, Ni HL. Dearomative 1,6-addition of P(O)–H to in situ formed p-QM-like ion pairs from 2-benzofuryl-ols to C3-phosphinoyl hydrobenzofurans. Org Chem Front 2021. [DOI: 10.1039/d1qo00076d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We report a dearomative C3-phosphorylation and a tandem C3-phosphorylation/aromatization of 2-benzofuryl-ols with P(O)–H species to afford C3-phosphinoyl hydrobenzofurans and benzofurans, respectively.
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4
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Tyagi A, Reshi NUD, Daw P, Bera JK. Palladium complexes with an annellated mesoionic carbene (MIC) ligand: catalytic sequential Sonogashira coupling/cyclization reaction for one-pot synthesis of benzofuran, indole, isocoumarin and isoquinolone derivatives. Dalton Trans 2020; 49:15238-15248. [DOI: 10.1039/d0dt02918a] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A Pd(ii) complex containing a mesoionic carbene and phosphine ligands is an efficient catalyst for tandem coupling/cyclization reaction.
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Affiliation(s)
- Akshi Tyagi
- Department of Chemistry and Centre for Environmental Sciences and Engineering
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Noor U Din Reshi
- Department of Chemistry and Centre for Environmental Sciences and Engineering
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Prosenjit Daw
- Department of Chemistry and Centre for Environmental Sciences and Engineering
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
| | - Jitendra K. Bera
- Department of Chemistry and Centre for Environmental Sciences and Engineering
- Indian Institute of Technology Kanpur
- Kanpur 208016
- India
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5
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Wen C, Jiang X, Wu K, Luo R, Li Q. Palladium-catalyzed cross-coupling reaction of alkenyl aluminums with 2-bromobenzo[b]furans. RSC Adv 2020; 10:19610-19614. [PMID: 35515440 PMCID: PMC9054126 DOI: 10.1039/d0ra02984j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Accepted: 05/16/2020] [Indexed: 12/18/2022] Open
Abstract
Highly efficient and simple cross-coupling reactions of 2-bromobenzo[b]furans with alkenylaluminum reagents for the synthesis of 2-alkenylbenzo[b]furan derivatives using PdCl2 (3 mol%)/XantPhos (6 mol%) as catalyst are reported. Excellent yields (up to 97%) were obtained for a wide range of substrates at 80 °C for 4 h in DCE. PdCl2 (3 mol%)/XantPhos (6 mol%) complexes was found to be a highly efficient catalyst for the synthesis of 2-alkenylbenzo[b]furans from 2-bromobenzo[b]furans and alkenylaluminums. The reaction was also found to be effective in gram-scale synthesis.![]()
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Affiliation(s)
- Chang Wen
- College of Chemistry and Environmental Protection Engineering
- Southwest University for Nationalities
- Chengdu
- China
| | - Xin Jiang
- College of Chemistry and Environmental Protection Engineering
- Southwest University for Nationalities
- Chengdu
- China
| | - Kun Wu
- College of Chemistry and Environmental Protection Engineering
- Southwest University for Nationalities
- Chengdu
- China
| | - Ruiqiang Luo
- College of Chemistry and Environmental Protection Engineering
- Southwest University for Nationalities
- Chengdu
- China
| | - Qinghan Li
- College of Chemistry and Environmental Protection Engineering
- Southwest University for Nationalities
- Chengdu
- China
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6
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Synthesis of benzofurans from terminal alkynes and iodophenols catalyzed by recyclable palladium nanoparticles supported on N,O-dual doped hierarchical porous carbon under copper- and ligand-free conditions. Catal Today 2019. [DOI: 10.1016/j.cattod.2018.04.036] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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7
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Kuan KK, Markwell-Heys AW, Cruickshank MC, Tran DP, Adlington RM, Baldwin JE, George JH. Biomimetic synthetic studies on meroterpenoids from the marine sponge Aka coralliphaga: Divergent total syntheses of siphonodictyal B, liphagal and corallidictyals A–D. Bioorg Med Chem 2019; 27:2449-2465. [DOI: 10.1016/j.bmc.2019.02.038] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 02/18/2019] [Indexed: 10/27/2022]
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8
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Chen H, Zhao S, Cheng S, Dai X, Xu X, Yuan W, Zhang X. Synthesis of Novel Pterocarpen Analogues
via
[3 + 2] Coupling‐Elimination Cascade of α,α‐Dicyanoolefins with Quinone Monoimines. J Heterocycl Chem 2019. [DOI: 10.1002/jhet.3543] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Hui Chen
- Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan ProvinceChengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Sihan Zhao
- Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan ProvinceChengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Shaobing Cheng
- Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan ProvinceChengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Xingjie Dai
- Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan ProvinceChengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 China
- University of Chinese Academy of Sciences Beijing 100049 China
| | - Xiaoying Xu
- Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan ProvinceChengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 China
| | - Weicheng Yuan
- Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan ProvinceChengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 China
| | - Xiaomei Zhang
- Key Laboratory for Asymmetric Synthesis and Chirotechnology of Sichuan ProvinceChengdu Institute of Organic Chemistry, Chinese Academy of Sciences Chengdu 610041 China
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9
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Affiliation(s)
- Jiasu Xu
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
| | - Viresh H. Rawal
- Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States
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10
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Fei C, Liu J, Peng H, Jiang D, Yin B. BINOL-phosphoric acids-catalyzed furylogous pinacol rearrangement of 1-[5-(hydroxy-diaryl-methyl)-furan-2-yl]-cyclobutanols into spiro cyclopentanones. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.10.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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11
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Song T, Yang Y. Metal Nanoparticles Supported on Biomass-Derived Hierarchical Porous Heteroatom-Doped Carbon from Bamboo Shoots: Design, Synthesis and Applications. CHEM REC 2018; 19:1283-1301. [PMID: 30276956 DOI: 10.1002/tcr.201800105] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Accepted: 09/12/2018] [Indexed: 01/21/2023]
Abstract
Heteroatom-doped porous carbon derived from biomass have recently received increasing attention due to their unique properties such as high electrical conductivity, large specific surface area, high porosity, and easy availability, which are appealing materials for versatile applications in catalysis, energy, separation and adsorption, and life sciences as well. On the basis of our previous work in this field, we summarized in this account our recent progress on design, synthesis of metal (e. g., Pd, Co) nanoparticles supported heteroatom-doped hierarchical porous carbon material derived from bamboo shoots and their applications for important organic transformations, including chemoselective semihydrogenation of alkynes, hydrosilylation of alkynes, cascade synthesis of benzofurans from terminal alkynes and iodophenols, selective hydrogenation of functionalized nitroarenes to form anilines, imines, and formamides. Finally, the current state and future challenges in this field are discussed. We hope this account could shed light on the rational design of novel non-noble metal based heterogeneous catalysts derived from biomass for efficient and sustainable organic transformations.
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Affiliation(s)
- Tao Song
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Yong Yang
- CAS Key Laboratory of Bio-based Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
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12
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Sun Z, Xiang K, Tao H, Guo L, Li Y. Synthesis of 2-substituted 3-chlorobenzofurans via TMSCl-mediated nucleophilic annulation of isatin-derived propargylic alcohols. Org Biomol Chem 2018; 16:6133-6139. [PMID: 30101259 DOI: 10.1039/c8ob01731j] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A TMSCl-mediated cascade annulation of isatin-derived propargylic alcohols for the synthesis of 2-substituted 3-chlorobenzofurans is now reported. Mechanistic investigations showed that this proceeded through a sequential Meyer-Schuster rearrangement/nucleophilic addition/intramolecular annulation. TMSCl not only acts as a promoter, but also acts as a chlorine source in this protocol.
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Affiliation(s)
- Zhou Sun
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. of China.
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13
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Christiaens M, Hullaert J, Van Hecke K, Laplace D, Winne JM. Stereoselective and Modular Assembly Method for Heterocycle-Fused Daucane Sesquiterpenoids. Chemistry 2018; 24:13783-13787. [DOI: 10.1002/chem.201803248] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Indexed: 01/31/2023]
Affiliation(s)
- Mien Christiaens
- Department of Organic and Macromolecular Chemistry; Ghent University; Krijgslaan 281 S4 Gent 9000 Belgium
| | - Jan Hullaert
- Department of Organic and Macromolecular Chemistry; Ghent University; Krijgslaan 281 S4 Gent 9000 Belgium
| | - Kristof Van Hecke
- Department of Chemistry; Ghent University; Krijgslaan 281 S3 Gent 9000 Belgium
| | - Duchan Laplace
- Department of Organic and Macromolecular Chemistry; Ghent University; Krijgslaan 281 S4 Gent 9000 Belgium
| | - Johan M. Winne
- Department of Organic and Macromolecular Chemistry; Ghent University; Krijgslaan 281 S4 Gent 9000 Belgium
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14
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Hullaert J, Winne JM. (5,6-Dihydro-1,4-dithiin-2-yl)methanol as a Versatile Allyl-Cation Equivalent in (3+2) Cycloaddition Reactions. Angew Chem Int Ed Engl 2018; 55:13254-13258. [PMID: 27653810 DOI: 10.1002/anie.201606411] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Revised: 08/12/2016] [Indexed: 12/15/2022]
Abstract
The title heterocyclic alcohol readily generates a sulfur-substituted allylic cation upon simple treatment with a protic acid, thus facilitating a synthetically useful stepwise (3+2) cycloaddition reaction pathway with a range of conjugated-olefin-type substrates. The introduction of an allyl fragment in this way provided rapid access to a variety of cyclopentanoid scaffolds. The cyclic nature of the cation precursor alcohol was shown to be instrumental for efficient cycloaddition reactions to take place, thus indicating an attractive strategy for controlling the reactivity of heteroatom-substituted allyl cations. The formal cycloaddition reaction is highly regio- and stereoselective and was also used for a short total synthesis of the natural product cuparene in racemic form through a cycloaddition-hydrodesulfurization sequence.
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Affiliation(s)
- Jan Hullaert
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, Gent, 9000, Belgium
| | - Johan M Winne
- Department of Organic and Macromolecular Chemistry, Ghent University, Krijgslaan 281 S4, Gent, 9000, Belgium.
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15
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Wang JL, Li HJ, Wu YC. Divergent Synthesis of Marine Natural Products Siphonodictyal B, Corallidictyals C/D, and Liphagal Based on the Early Presence of an Aldehyde Group Instead of a Late-Stage Introduction. J Org Chem 2018; 83:8716-8723. [DOI: 10.1021/acs.joc.8b00989] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jun-Li Wang
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
| | - Hui-Jing Li
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
| | - Yan-Chao Wu
- School of Marine Science and Technology, Harbin Institute of Technology, Weihai 264209, China
- Beijing National Laboratory for Molecular Sciences, ICCAS, Beijing 100190, China
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16
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Karimov RR, Tan DS, Gin DY. Synthesis of the hexacyclic triterpene core of the jujuboside saponins via tandem Wolff rearrangement-intramolecular ketene hetero-Diels-Alder reaction. Tetrahedron 2018; 74:3370-3383. [PMID: 30467444 DOI: 10.1016/j.tet.2018.04.051] [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] [Indexed: 11/16/2022]
Abstract
The jujubosides are saponin natural products reported to have immunoadjuvant, anticancer, antibacterial, antifungal, and antisweet activities. The triterpene component, jujubogenin contains a unique tricyclic ketal motif comprising the DEF ring system. Herein, we describe our efforts toward the total synthesis of jujubogenin, using a sterically-demanding intermolecular Diels-Alder reaction to assemble the C-ring and a tandem Wolff rearrangement-intramolecular ketene hetero-Diels-Alder reaction to form the DF-ring system. Acid-catalyzed cyclization of the resulting bicyclic enol ether then closes the E-ring to provide the hexacyclic core of jujubogenin.
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Affiliation(s)
- Rashad R Karimov
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, USA
| | - Derek S Tan
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, USA.,Chemical Biology Program and Tri-Institutional Research Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, USA
| | - David Y Gin
- Tri-Institutional PhD Program in Chemical Biology, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, USA.,Chemical Biology Program and Tri-Institutional Research Program, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, Box 422, New York, New York 10065, USA
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17
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Zong Y, Wang W, Xu T. Total Synthesis of Bioactive Marine Meroterpenoids: The Cases of Liphagal and Frondosin B. Mar Drugs 2018; 16:md16040115. [PMID: 29614734 PMCID: PMC5923402 DOI: 10.3390/md16040115] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 03/28/2018] [Accepted: 03/28/2018] [Indexed: 01/09/2023] Open
Abstract
Liphagal and frondosin B are two marine-derived secondary metabolites sharing a very similar polyfused-benzofuran skeleton. The two tetracyclic meroterpenoids were isolated from marine sponges, both featuring a 6-5-7-6 fused ring system. A preliminary bioactive study shows that (+)-liphagal is a selective kinase (PI3K α) inhibitor, while (+)-frondosin B is shown to inhibit the binding of the cytokine interleukin-8 (IL-8) to its receptor, CX-CLR1/2. The unique structures and interesting biological profiles of these two meroterpenoids have attracted considerable attention from synthetic chemists. Herein we summarize the synthetic efforts with respect to (+)-liphagal and (+)-frondosin B during the past two decades.
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Affiliation(s)
- Yan Zong
- Key Laboratory of Marine Drugs, Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
| | - Weijia Wang
- Key Laboratory of Marine Drugs, Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
| | - Tao Xu
- Key Laboratory of Marine Drugs, Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
- Laboratory for Marine Drugs and Bioproducts of Qingdao, National Laboratory for Marine Science and Technology (QNLM), 1 Wenhai Road, Qingdao 266237, China.
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18
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Katoh T, Narita K. Total Syntheses of Liphagal: A Potent and Selective Phosphoinositide 3-Kinase α (PI3Kα) Inhibitor from the Marine Sponge Aka coralliphaga. HETEROCYCLES 2018. [DOI: 10.3987/rev-17-873] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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19
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Yin Z, He Y, Chiu P. Application of (4+3) cycloaddition strategies in the synthesis of natural products. Chem Soc Rev 2018; 47:8881-8924. [DOI: 10.1039/c8cs00532j] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
This review summarizes the applications of (4+3) cycloadditions, both classical and formal, in the syntheses of natural products in the last two decades.
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Affiliation(s)
- Zengsheng Yin
- Department of Chemistry
- State Key Laboratory of Synthetic Chemistry
- The University of Hong Kong
- P. R. China
| | - Yun He
- Department of Chemistry
- State Key Laboratory of Synthetic Chemistry
- The University of Hong Kong
- P. R. China
| | - Pauline Chiu
- Department of Chemistry
- State Key Laboratory of Synthetic Chemistry
- The University of Hong Kong
- P. R. China
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20
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Radhakrishna L, Pandey MK, Balakrishna MS. 1,2,3-Triazole based bisphosphine, 5-(diphenylphosphanyl)-1-(2-(diphenylphosphanyl)-phenyl)-4-phenyl-1H-1,2,3-triazole: an ambidentate ligand with switchable coordination modes. RSC Adv 2018; 8:25704-25718. [PMID: 35539783 PMCID: PMC9082604 DOI: 10.1039/c8ra04086a] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 07/06/2018] [Indexed: 12/05/2022] Open
Abstract
The reaction of 1-(2-bromophenyl)-4-phenyl-1H-1,2,3-triazole (1) with Ph2PCl yielded bisphosphine, 5-(diphenylphosphanyl)-1-(2-(diphenylphosphanyl)phenyl)-4-phenyl-1H-1,2,3-triazole (2). Bisphosphine 2 exhibits ambidentate character in either the κ2-P,N or κ2-P,P coordination mode. Treatment of 2 with [M(CO)4(piperidine)2] (M = Mo and W) yielded κ2-P,N and κ2-P,P coordinated Mo0 and W0 complexes [M(CO)4(2)] [M = W-κ2-P,N (4); Mo-κ2-P,P (5); W-κ2-P,P (6)] depending on the reaction conditions. Formation and stability of κ2-P,P coordinated Mo0 and W0 complexes were assessed by time dependent 31P{1H} NMR experiments and DFT studies. The complex 4 on treatment with [AuCl(SMe2)] afforded the hetero-bimetallic complex [μ-PN,P-{o-Ph2P(C6H4){1,2,3-N3C(Ph)C(PPh2AuCl)}-κ2-P,N}W(CO)4] (7). The 1 : 1 reaction between 2 and [CpRu(PPh3)2Cl] yielded [(η5-C5H5)RuCl{o-Ph2P(C6H4){1,2,3-N3C(Ph)C(PPh2)}}-κ2-P,P] (8), whereas the similar reaction with [Ru(η6-p-cymene)Cl2]2 in a 2 : 1 molar ratio produced a cationic complex [(η6-p-cymene)RuCl{o-Ph2P(C6H4){1,2,3-N3C(Ph)C(PPh2)}}-κ2-P,N]Cl (9). Similarly, treatment of 2 with [M(COD)(Cl)2] (M = Pd and Pt) in a 1 : 1 molar ratio yielded PdII and PtII complexes [{o-Ph2P(C6H4){1,2,3-N3C(Ph)C(PPh2)}-κ2-P,P}PdCl2] (10) and [{o-Ph2P(C6H4){1,2,3-N3C(Ph)C(PPh2)}-κ2-P,P}PtCl2] (11). The reaction of 2 with 2 equiv. of [AuCl(SMe2)] afforded [Au2Cl2{o-Ph2P(C6H4){1,2,3-N3C(Ph)C(PPh2)}}-μ-P,P] (12). Most of the complexes have been structurally characterized. Palladium complex 10 shows excellent catalytic activity towards Cu-free Sonogashira alkynylation/cyclization reactions. This paper describes the synthesis of a triazole based bisphosphine and its transition metal chemistry and catalytic utility in Cu-free Sonogashira alkynylation/cyclization reaction.![]()
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Affiliation(s)
| | - Madhusudan K. Pandey
- Phosphorus Laboratory
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
| | - Maravanji S. Balakrishna
- Phosphorus Laboratory
- Department of Chemistry
- Indian Institute of Technology Bombay
- Mumbai 400076
- India
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Sun Z, Tian S, Li S, Liu Y, Zhang Y, Li Y. Facile synthesis of thiochromanyl-spirooxindoles via K 2 CO 3 catalyzed tandem sulfa-Michael/Aldol reaction. Tetrahedron Lett 2017. [DOI: 10.1016/j.tetlet.2017.07.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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22
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Huynh KQ, Seizert CA, Ozumerzifon TJ, Allegretti PA, Ferreira EM. Platinum-Catalyzed α,β-Unsaturated Carbene Formation in the Formal Syntheses of Frondosin B and Liphagal. Org Lett 2016; 19:294-297. [PMID: 27997203 DOI: 10.1021/acs.orglett.6b03682] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Formal syntheses of tetracyclic terpenoids frondosin B and liphagal are described. Both synthetic routes rely on the use of platinum-catalyzed α,β-unsaturated carbene formation for the key C-C bond forming transformations. The successful route toward frondosin B utilizes a formal (4 + 3) cycloaddition, while the liphagal synthesis features the vinylogous addition of an enol nucleophile as a key step. Both synthetic routes are discussed, revealing insights into structural requirements in the catalytic α,β-unsaturated carbene reaction manifold.
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Affiliation(s)
- Khoi Q Huynh
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
| | - Curtis A Seizert
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
| | - Tarik J Ozumerzifon
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
| | - Paul A Allegretti
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
| | - Eric M Ferreira
- Department of Chemistry, University of Georgia , Athens, Georgia 30602, United States
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23
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Hullaert J, Winne JM. (5,6-Dihydro-1,4-dithiin-2-yl)methanol as a Versatile Allyl-Cation Equivalent in (3+2) Cycloaddition Reactions. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201606411] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Jan Hullaert
- Department of Organic and Macromolecular Chemistry; Ghent University; Krijgslaan 281 S4 Gent 9000 Belgium
| | - Johan M. Winne
- Department of Organic and Macromolecular Chemistry; Ghent University; Krijgslaan 281 S4 Gent 9000 Belgium
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24
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Tzouma E, Mavridis I, Vidali VP, Pitsinos EN. Diels–Alder reaction between 1,3,3-trisubstituted-2-vinylcyclohexenes and quinones under exceptionally mild conditions: a concise entry to the cassane-type furanoditerpenoid skeleton. Tetrahedron Lett 2016. [DOI: 10.1016/j.tetlet.2016.06.133] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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25
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Markwell-Heys AW, George JH. Some chemical speculation on the biosynthesis of corallidictyals A–D. Org Biomol Chem 2016; 14:5546-9. [DOI: 10.1039/c6ob00171h] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The efficient conversion of siphonodictyal B into the spirocyclic natural products corallidictyals A–D has been achieved via oxidative and acid catalyzed cyclizations.
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26
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Liu Y, Sun Z, Li S, Xiang K, Zhang Y, Li Y. Mg(ClO4)2-promoted [4 + 3] cycloaddition of oxindole derivatives with conjugated dienes: concise synthesis of spirocycloheptane oxindole derivatives. RSC Adv 2016. [DOI: 10.1039/c6ra03259a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Novel Mg(ClO4)2-promoted [4 + 3] cycloaddition reaction of oxindole derivatives and cyclopentadiene was achieved for the construction of the spirocycloheptane oxindole skeleton.
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Affiliation(s)
- Yun Liu
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou
- P. R. China
| | - Zhou Sun
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou
- P. R. China
| | - Song Li
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou
- P. R. China
| | - Kuirong Xiang
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou
- P. R. China
| | - Yuan Zhang
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou
- P. R. China
| | - Ying Li
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering
- Lanzhou University
- Lanzhou
- P. R. China
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27
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Markwell-Heys AW, Kuan KKW, George JH. Total Synthesis and Structure Revision of (-)-Siphonodictyal B and Its Biomimetic Conversion into (+)-Liphagal. Org Lett 2015; 17:4228-31. [PMID: 26295981 DOI: 10.1021/acs.orglett.5b01973] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The structure of siphonodictyal B has been reassigned on the basis of the total synthesis of both possible C-8 epimers. The revised structure of siphonodictyal B was converted into liphagal by acid catalyzed rearrangement of a proposed epoxide intermediate. This biomimetic cascade features a succession of four distinct reactions (epoxidation, o-quinone methide formation, ring expansion, and benzofuran formation) that occur in a one-pot operation under mild conditions. During these studies we also isolated a surprisingly stable o-quinone methide that supports our mechanistic proposal for liphagal biosynthesis.
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Affiliation(s)
| | - Kevin K W Kuan
- Department of Chemistry, University of Adelaide , Adelaide, SA 5005, Australia
| | - Jonathan H George
- Department of Chemistry, University of Adelaide , Adelaide, SA 5005, Australia
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28
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Agasti S, Maity S, Szabo KJ, Maiti D. Palladium-Catalyzed Synthesis of 2,3-Disubstituted Benzofurans: An Approach Towards the Synthesis of Deuterium Labeled Compounds. Adv Synth Catal 2015; 357:2331-2338. [PMID: 26347405 PMCID: PMC4552971 DOI: 10.1002/adsc.201500308] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2015] [Revised: 04/30/2015] [Indexed: 11/21/2022]
Abstract
Palladium-catalyzed oxidative annulations between phenols and alkenylcarboxylic acids produced a library of benzofuran compounds. Depending on the nature of the substitution of the phenol precursor, either 2,3-dialkylbenzofurans or 2-alkyl-3-methylene-2,3-dihydrobenzofurans can be synthesized with excellent regioselectivity. Reactions between conjugated 5-phenylpenta-2,4-dienoic acids and phenol gave 3-alkylidenedihydrobenzofuran alkaloid motifs while biologically active 7-arylbenzofuran derivatives were prepared by starting from 2-phenylphenols. More interestingly, selective incorporation of deuterium from D2O has been discovered, which offers an attractive one-step method to access deuterated compounds.
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Affiliation(s)
- Soumitra Agasti
- Department of Chemistry, Indian Institute of Technology Bombay Powai, Mumbai - 400076, India E-mail:
| | - Soham Maity
- Department of Chemistry, Indian Institute of Technology Bombay Powai, Mumbai - 400076, India E-mail:
| | - Kalman J Szabo
- Department of Organic Chemistry, Stockholm University SE-106 91 Stockholm, Sweden E-mail:
| | - Debabrata Maiti
- Department of Chemistry, Indian Institute of Technology Bombay Powai, Mumbai - 400076, India E-mail:
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29
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Palframan MJ, Pattenden G. The versatility of furfuryl alcohols and furanoxonium ions in synthesis. Chem Commun (Camb) 2015; 50:7223-42. [PMID: 24728307 DOI: 10.1039/c4cc01196a] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Substituted furfuryl alcohols are extraordinarily versatile starting materials in synthesis. They are precursors to furanoxonium ion intermediates which are implicated in the Piancatelli reaction (leading to 2-cyclopentenones) and in the synthesis of novel dihydrofuran-based exo enol ether/cyclic ketal natural products. They are also intermediates in a recently discovered (4+3) cycloaddition reaction with 1,3-dienes leading to furan ring-fused cycloheptenes. Here we provide a perspective on recent developments in these areas of synthesis, alongside recent applications of the Achmatowicz reaction and [5+2] cycloaddition reactions of the resulting oxidopyrylium ions.
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30
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Rao MLN, Dasgupta P. A concise route to functionalized benzofurans directly from gem-dibromoalkenes and phenols. RSC Adv 2015. [DOI: 10.1039/c5ra13213d] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
A tandem strategy for the construction of benzofuran motifs has been developed directly from gem-dibromoalkenes and phenols under palladium-catalyzed conditions.
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Affiliation(s)
- Maddali L. N. Rao
- Department of Chemistry
- Indian Institute of Technology Kanpur
- Kanpur
- India
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31
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Cao KS, Bian HX, Zheng WH. Mild arylboronic acid catalyzed selective [4 + 3] cycloadditions: access to cyclohepta[b]benzofurans and cyclohepta[b]indoles. Org Biomol Chem 2015; 13:6449-52. [DOI: 10.1039/c5ob00653h] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The first example of arylboronic acid catalyzed [4 + 3] cycloaddition reaction is reported.
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Affiliation(s)
- Kou-Sen Cao
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210093
- P. R. China
| | - Hong-Xu Bian
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210093
- P. R. China
| | - Wen-Hua Zheng
- State Key Laboratory of Coordination Chemistry
- School of Chemistry and Chemical Engineering
- Nanjing University
- Nanjing 210093
- P. R. China
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32
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Zhang J, Shao J, Xue J, Wang Y, Li Y. One pot hydroamination/[4 + 3] cycloaddition: synthesis towards the cyclohepta[b]indole core of silicine and ervatamine. RSC Adv 2014. [DOI: 10.1039/c4ra13249a] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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33
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Zhou R, Wang W, Jiang ZJ, Wang K, Zheng XL, Fu HY, Chen H, Li RX. One-pot synthesis of 2-substituted benzo[b]furans via Pd-tetraphosphine catalyzed coupling of 2-halophenols with alkynes. Chem Commun (Camb) 2014; 50:6023-6. [PMID: 24770847 DOI: 10.1039/c4cc00815d] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A catalyst composed of [Pd(η(3)-C3H5)Cl]2 and N,N,N',N'-tetra(diphenylphosphinomethyl)pyridine-2,6-diamine (L) was found to be effective for one-pot synthesis of 2-substituted benzo[b]furans from 2-halophenols and alkynes. For 2-bromo-3-hydroxypyridine, the catalyst loading could be as low as 1 ppm and the turnover number (TON) was up to 870,000.
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Affiliation(s)
- Rong Zhou
- Key Lab of Green Chemistry and Technology, Ministry of Education, Sichuan University, Chengdu, China.
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34
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Kamishima T, Kikuchi T, Narita K, Katoh T. Biogenetically Inspired Total Synthesis of (+)-Liphagal: A Potent and Selective Phosphoinositide 3-Kinase α (PI3Kα) Inhibitor from the Marine SpongeAka coralliphaga. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402082] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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35
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Hullaert J, Laplace DR, Winne JM. A Three-Step Synthesis of the Guaianolide Ring System. European J Org Chem 2014. [DOI: 10.1002/ejoc.201402170] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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36
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Xie YX, Tang RY, Song RJ, Xiang JN, Li JH. Synthesis of Benzocyclohepta[b]indoles by Lewis Acid Catalyzed Annulation of Two 3-(1H-Isochromen-1-yl)-1H-indoles. J Org Chem 2014; 79:686-91. [DOI: 10.1021/jo4024667] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ye-Xiang Xie
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Ri-Yuan Tang
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, China
- College
of Chemistry and Materials Engineering, Wenzhou University, Wenzhou 325035, China
| | - Ren-Jie Song
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Jian-Nan Xiang
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, China
| | - Jin-Heng Li
- State
Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry
and Chemical Engineering, Hunan University, Changsha 410082, China
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37
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The Synthesis of Seven-Membered Rings in Natural Products. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/b978-0-444-63281-4.00014-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
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38
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Laplace DR, Verbraeken B, Van Hecke K, Winne JM. Total Synthesis of (+/−)-Frondosin B and (+/−)-5-epi-Liphagal by Using a Concise (4+3) Cycloaddition Approach. Chemistry 2013; 20:253-62. [DOI: 10.1002/chem.201303273] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Indexed: 11/07/2022]
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39
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Gao X, Harmata M. Formation and ring-opening of 8-oxabicyclo[3.2.1]oct-6-en-3-ones from (4+3)-cycloaddition of furan and chlorocyclopentanone derivatives. Tetrahedron 2013. [DOI: 10.1016/j.tet.2013.05.051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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40
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Dhiman S, Ramasastry SSV. Taming furfuryl cations for the synthesis of privileged structures and novel scaffolds. Org Biomol Chem 2013; 11:4299-303. [PMID: 23736893 DOI: 10.1039/c3ob40814k] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Furfuryl cations are generated via a highly efficient bismuth-catalyzed reaction of furfuryl alcohols. This systematic study provides insight on the reactivity profile of furfuryl cations towards nucleophilic substitution reactions. Novel C-C, C-N, C-O and C-S bond forming reactions of furfuryl cations have been developed, thus providing access to a diverse array of building blocks for further manipulations.
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Affiliation(s)
- Seema Dhiman
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER) Mohali, Sector 81, S A S Nagar, Manuali 140 306, Punjab, India
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41
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Gong W, Liu Y, Zhang J, Jiao Y, Xue J, Li Y. Regio- and Stereoselective[4+3] Cycloaddition Towards Fused 5,7,6-Tricyclic Skeletons. Chem Asian J 2013; 8:546-51. [DOI: 10.1002/asia.201201066] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 11/24/2012] [Indexed: 11/11/2022]
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42
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Zeng W, Wu W, Jiang H, Huang L, Sun Y, Chen Z, Li X. Facile synthesis of benzofurans via copper-catalyzed aerobic oxidative cyclization of phenols and alkynes. Chem Commun (Camb) 2013; 49:6611-3. [DOI: 10.1039/c3cc42326c] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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