1
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Chen X, Zhou Y, Jin J, Farshadfar K, Ariafard A, Rao W, Chan PWH. Gold Catalyzed Cyclopropanation/[5+3] Cycloaddition of 1,4,9‐ and 1,4,10‐Allenenynes to Bicyclo[3.3.1]nonane Derivatives. Adv Synth Catal 2020. [DOI: 10.1002/adsc.201901263] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Xianxiao Chen
- Jiangsu Key Laboratory of Biomass-based Green Fuels and Chemicals, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
| | - Yuanyuan Zhou
- Jiangsu Key Laboratory of Biomass-based Green Fuels and Chemicals, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
| | - Jianwen Jin
- School of Chemistry Monash University Clayton, Victoria 3800 Australia
| | - Kaveh Farshadfar
- Department of Chemistry Islamic Azad University, Poonak Tehran Iran
| | - Alireza Ariafard
- Department of Chemistry Islamic Azad University, Poonak Tehran Iran
- School of Physical Sciences-Chemistry University of Tasmania Hobart, Tasmania 7001 Australia
| | - Weidong Rao
- Jiangsu Key Laboratory of Biomass-based Green Fuels and Chemicals, College of Chemical Engineering Nanjing Forestry University Nanjing 210037 People's Republic of China
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2
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Yang QQ, Yin X, He XL, Du W, Chen YC. Asymmetric Formal [5 + 3] Cycloadditions with Unmodified Morita–Baylis–Hillman Alcohols via Double Activation Catalysis. ACS Catal 2019. [DOI: 10.1021/acscatal.8b04942] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Affiliation(s)
- Qian-Qian Yang
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Xiang Yin
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Xiao-Long He
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Wei Du
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
| | - Ying-Chun Chen
- Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China
- College of Pharmacy, Third Military Medical University, Shapingba, Chongqing 400038, China
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3
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Affiliation(s)
- Nirupam De
- Department of Chemistry, Kangwon National University, 1 Kangwondaehak-gil, Chuncheon 24341, Republic of Korea
| | - Eun Jeong Yoo
- Department of Chemistry, Kangwon National University, 1 Kangwondaehak-gil, Chuncheon 24341, Republic of Korea
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4
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Lee DJ, Ko D, Yoo EJ. Rhodium(II)-Catalyzed Cycloaddition Reactions of Non-classical 1,5-Dipoles for the Formation of Eight-Membered Heterocycles. Angew Chem Int Ed Engl 2015; 54:13715-8. [DOI: 10.1002/anie.201506764] [Citation(s) in RCA: 86] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Indexed: 11/11/2022]
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5
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Lee DJ, Ko D, Yoo EJ. Rhodium(II)-Catalyzed Cycloaddition Reactions of Non-classical 1,5-Dipoles for the Formation of Eight-Membered Heterocycles. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201506764] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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6
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Yin X, Zheng Y, Feng X, Jiang K, Wei XZ, Gao N, Chen YC. Asymmetric [5+3] Formal Cycloadditions with Cyclic Enones through Cascade Dienamine-Dienamine Catalysis. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201403753] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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7
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Yin X, Zheng Y, Feng X, Jiang K, Wei XZ, Gao N, Chen YC. Asymmetric [5+3] Formal Cycloadditions with Cyclic Enones through Cascade Dienamine-Dienamine Catalysis. Angew Chem Int Ed Engl 2014; 53:6245-8. [DOI: 10.1002/anie.201403753] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Indexed: 11/09/2022]
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8
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Chen W, Sana K, Jiang Y, Meyer EVS, Lapp S, Galinski MR, Liebeskind LS. Regio- and Stereospecific Uncatalyzed Reactions of Electron-Rich Arenes and Olefins at Organomolybdenum Enantiomeric Scaffolds. Organometallics 2013. [DOI: 10.1021/om401087h] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Wenyong Chen
- Sanford S. Atwood Chemistry Center, Emory University, 1515 Dickey
Drive, Atlanta, Georgia 30322, United States
| | - Kasinath Sana
- Sanford S. Atwood Chemistry Center, Emory University, 1515 Dickey
Drive, Atlanta, Georgia 30322, United States
| | - Yi Jiang
- Sanford S. Atwood Chemistry Center, Emory University, 1515 Dickey
Drive, Atlanta, Georgia 30322, United States
| | - Esmerelda V. S. Meyer
- Emory Vaccine Center at Yerkes National Primate
Research Center, Emory University, Atlanta, Georgia 30329, United States
| | - Stacey Lapp
- Emory Vaccine Center at Yerkes National Primate
Research Center, Emory University, Atlanta, Georgia 30329, United States
| | - Mary R. Galinski
- Emory Vaccine Center at Yerkes National Primate
Research Center, Emory University, Atlanta, Georgia 30329, United States
- Emory University School of Medicine, Department
of Medicine, Division of Infectious Diseases, Emory University, Atlanta, Georgia 30322, United States
| | - Lanny S. Liebeskind
- Sanford S. Atwood Chemistry Center, Emory University, 1515 Dickey
Drive, Atlanta, Georgia 30322, United States
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9
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Zhu L, Song L, Tong R. Diastereoselective Reductive Ring Expansion of Spiroketal Dihydropyranones to cis-Fused Bicyclic Ethers. Org Lett 2012; 14:5892-5. [DOI: 10.1021/ol302813e] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Liangyu Zhu
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Liyan Song
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Rongbiao Tong
- Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
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10
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Wong H, Garnier-Amblard EC, Liebeskind LS. Organometallic enantiomeric scaffolding: a strategy for the enantiocontrolled construction of regio- and stereodivergent trisubstituted piperidines from a common precursor. J Am Chem Soc 2011; 133:7517-27. [PMID: 21513336 PMCID: PMC3107969 DOI: 10.1021/ja201012p] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Reported herein is a general and efficient method to construct 2,3,6-trisubstituted piperidines in a substituent-independent fashion. From the high enantiopurity organometallic scaffold (-)-Tp(CO)(2)[(η-2,3,4)-(1S,2S)-1-benzyloxycarbonyl-5-oxo-5,6-dihydro-2H-pyridin-2-yl)molybdenum (Tp = hydridotrispyrazolylborato), a variety of TpMo(CO)(2)-based 2,3,6-trifunctionalized complexes of the (η-3,4,5-dihydropyridinyl) ligand were easily obtained in 5 steps through a sequence of highly regio- and stereospecific metal-influenced transformations (15 examples). From the 2,3,6-trifunctionalized molybdenum complexes, either 2,6-cis-3-trans or 2,3,6-cis systems were selectively obtained through the choice of an appropriate stereodivergent demetalation protocol. The potential of this strategy in synthetic chemistry was demonstrated by the short total synthesis of four natural and one non-natural alkaloids: indolizidines (±)-209I and (±)-8-epi-219F in the racemic series, and enantiocontrolled syntheses of (-)-indolizidine 251N, (-)-quinolizidine 251AA, and (-)-dehydroindolizidine 233E.
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Affiliation(s)
| | | | - Lanny S. Liebeskind
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia, 30322
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11
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Meng X, Kim S. Tungsten and molybdenum catalyst-mediated cyclisation of N-propargyl amides. Org Biomol Chem 2011; 9:4429-31. [DOI: 10.1039/c1ob05512g] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Yu ZX, Wang Y, Wang Y. Transition-metal-catalyzed cycloadditions for the synthesis of eight-membered carbocycles. Chem Asian J 2010; 5:1072-88. [PMID: 20432504 DOI: 10.1002/asia.200900712] [Citation(s) in RCA: 144] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Eight-membered carbocycles are found in a wide variety of natural products that exhibit a broad range of biological and medicinal activities (cf. the most potent anticancer drug, taxol). However, the synthesis of eight-membered carbocycles is quite challenging as traditional approaches are met with entropic and enthalpic penalties in the ring-forming transition states. These negative effects can be totally or partially avoided with the implementation of transition-metal-catalyzed/mediated cycloadditions. In this Focus Review, examples of elegant and efficient metal-catalyzed and some metal-mediated cycloadditions (including Ni- catalyzed [4+4] and Rh-catalyzed [4+2+2] and [5+2+1] reactions) are presented to illustrate this. Application of these cycloaddition reactions in total synthesis is also presented to show the significance of these reactions in addressing challenges in natural product synthesis.
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Affiliation(s)
- Zhi-Xiang Yu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Bioorganic Chemistry and Molecular Engineering of the Ministry of Education, College of Chemistry, Peking University, Beijing 100871, China.
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13
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Coombs TC, Huang W, Garnier-Amblard EC, Liebeskind LS. Novel Substitutions of 1-Alkoxy- and 1-Arylsulfonyloxy-η-Allylmolybdenum Complexes. A Case for η-Alkenyl Carbene Complexes as Intermediates. Organometallics 2010; 29:5083-5097. [PMID: 21116457 DOI: 10.1021/om100305f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A series of acyclic and cyclic 1-alkoxy- and 1-arylsulfonyloxy-substituted TpMo(CO)(2)(η(3)-allyl) complexes was synthesized and characterized, and exchange of the oxygenated substituent was investigated under a variety of reaction conditions. 1-Alkoxy-substituted η(3)-allyl and η(3)-butenyl complexes participated in direct, uncatalyzed exchange of the alkoxy substituent with benzylamine, but required a Lewis acid for exchange with alcohols. The 1-alkoxy-substituted η(3)-cyclohexenyl complex was unreactive towards exchange under all conditions investigated. The corresponding acyclic arylsulfonyloxy-substituted complexes underwent direct, uncatalyzed exchange with both benzylamine and alcohols, while the arylsulfonyloxy-substituted cyclohexenyl compounds participated in direct substitution with benzylamine, but not alcohols. High enantiopurity acyclic and cyclic alkoxy- and arylsulfonyloxy-substituted complexes provided exchange products with predominant, but incomplete, losses in enantiomeric excess in all cases examined. Mechanisms accounting for the observed reactivity trends and for the losses in enantiomeric excess are discussed. Reaction of alkoxy-substituted complexes through an associative mechanism and of arylsulfonyloxy-substituted compounds through a dissociative mechanism is suggested.
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Affiliation(s)
- Thomas C Coombs
- Sanford S. Atwood Chemistry Center, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322
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14
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Chen W, Liebeskind LS. A new reaction motif: "homo-S(N)2'-like" direct nucleophilic addition to neutral eta(3)-allylmolybdenum complexes. total synthesis of the antimalarial (+)-isofebrifugine. J Am Chem Soc 2009; 131:12546-7. [PMID: 19678704 DOI: 10.1021/ja9056322] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Charge neutral TpMo(CO)(2)(5-acyloxy-eta(3)-pyranyl) and TpMo(CO)(2)(5-acyloxy-eta(3)-pyridinyl) scaffolds undergo a novel intermolecular "homo-S(N)2'-like" reaction with a variety of carbon nucleophiles. Combined with an annulative demetalation, the homo-S(N)2'-like substitution/annulative demetalation sequence rapidly generates 2,7-dioxabicyclo[4.3.0]nonane and 2-aza-7-oxabicyclo[4.3.0]nonane frameworks in good to excellent yields with high enantiopurity. An enantiocontrolled total synthesis of the antimalarial alkaloid (+)-isofebrifugine was achieved utilizing this reaction cascade.
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Affiliation(s)
- Wenyong Chen
- Sanford S. Atwood Chemistry Center, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, USA
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15
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Cheng B, Liebeskind LS. Organometallic enantiomeric scaffolding. A molybdenum-mediated intramolecular nucleophilic ketalization-demetalation cascade. Total synthesis of (+)-(1R,2S,5S,7R)-2-hydroxy-exo-brevicomin. Org Lett 2009; 11:3682-5. [PMID: 19627126 PMCID: PMC2736330 DOI: 10.1021/ol901523g] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
TpMo(CO)(2)(5-oxo-eta(3)-pyranyl) scaffolds bearing an internal alkoxide undergo a novel intramolecular nucleophilic ketalization reaction. The anionic intermediate is easily demetalated, rapidly providing the 6,8-dioxabicyclo[3.2.1]oct-3-en-2-one framework in moderate to good yields with high enantiopurity. An enantiocontrolled total synthesis of (+)-(1R,2S,5S,7R)-2-hydroxy-exo-brevicomin was accomplished utilizing the reaction sequence.
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Affiliation(s)
- Bo Cheng
- Emory University, Department of Chemistry, 1515 Dickey Drive, Atlanta, Georgia 30322, USA
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16
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Coombs TC, Zhang Y, Garnier-Amblard EC, Liebeskind LS. Organometallic enantiomeric scaffolding. Sequential semipinacol/1,5-"Michael-like" reactions as a strategic approach to bridgehead-quaternary center aza[3.3.1]bicyclics: application to the total synthesis of (-)-adaline. J Am Chem Soc 2009; 131:876-7. [PMID: 19123794 DOI: 10.1021/ja808533z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A nontraditional approach to the enantiocontrolled construction of quaternary center-bearing heteroatom-bridged bicyclo[3.3.1]nonanes (homotropanes) is reported that is based on organometallic enantiomeric scaffolding. This strategy takes advantage of the unique reactivity profiles of TpMo(CO)(2)(5-oxo-eta(3)-pyranyl) and TpMo(CO)(2)(5-oxo-eta(3)-pyridinyl) scaffolds, and features a molybdenum-mediated semipinacol/1,5-"Michael-like" reaction sequence to establish the quaternary center and synthesize the bridged bicyclic structure. An asymmetric total synthesis of (-)-adaline highlights this methodology.
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Affiliation(s)
- Thomas C Coombs
- Sanford S. Atwood Chemistry Center, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, USA
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17
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Garnier EC, Liebeskind LS. Organometallic enantiomeric scaffolding: general access to 2-substituted oxa- and azabicyclo[3.2.1]octenes via a Brønsted acid catalyzed [5 + 2] cycloaddition reaction. J Am Chem Soc 2008; 130:7449-58. [PMID: 18479131 DOI: 10.1021/ja800664v] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
6-Substituted TpMo(CO) 2(eta-2,3,4-pyranyl)- and TpMo(CO) 2(eta-2,3,4-pyridinyl) scaffolds (Tp = hydridotrispyrazolylborato) function as reaction partners in an efficient regio- and stereocontrolled synthesis of functionalized oxa- and azabicyclo[3.2.1]octenes through a novel Brønsted acid catalyzed [5 + 2] cycloaddition reaction. Excellent exo-selectivities are obtained, and the reaction gives products with complete retention of enantiomeric purity when carried out with chiral, nonracemic scaffolds. The substituent at C-6 of the eta (3)-coordinated heterocyclic scaffold not only influences [5 + 2] reactivity but also plays a critical role in the demetalation step directing the reaction to only one of two possible products.
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Affiliation(s)
- Ethel C Garnier
- Emory University, Department of Chemistry, 1515 Dickey Drive, Atlanta, Georgia 30322, USA
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18
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Coombs TC, Lee MD, Wong H, Armstrong M, Cheng B, Chen W, Moretto AF, Liebeskind LS. Practical, scalable, high-throughput approaches to eta3-pyranyl and eta3-pyridinyl organometallic enantiomeric scaffolds using the Achmatowicz reaction. J Org Chem 2008; 73:882-8. [PMID: 18171075 DOI: 10.1021/jo702006z] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A unified strategy for the high-throughput synthesis of multigram quantities of the eta(3)-oxopyranyl- and eta(3)-oxopyridinylmolybdenum complexes TpMo(CO)(2)(eta(3)-oxopyranyl) and TpMo(CO)(2)(eta(3)-oxopyridinyl) is described (Tp = hydridotrispyrazolylborato). The strategy uses the oxa- and aza-Achmatowicz reaction for the preparation of these organometallic enantiomeric scaffolds, in both racemic and high enantiopurity versions.
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Affiliation(s)
- Thomas C Coombs
- Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, Georgia 30322, USA
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19
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Arrayás RG, Yin J, Liebeskind LS. The enantiomeric scaffold approach to highly functionalized 1-oxadecalines: enantio- and regiocontrolled [4 + 2] cycloadditions of 5-alkenyl-eta3-pyranylmolybdenum complexes. J Am Chem Soc 2007; 129:1816-25. [PMID: 17284010 PMCID: PMC2758531 DOI: 10.1021/ja067104f] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
TpMo(CO)2(5-alkenyl-eta-2,3,4-pyranyl) diene complexes function as excellent chiral scaffolds for the efficient regio- and enantiocontrolled synthesis of highly functionalized 1-oxadecaline derivatives through a novel transition metal-mediated Diels-Alder reaction. Very good to excellent yields and excellent levels of endo selectivity are obtained, and the reaction gives products with complete retention of enantiomeric purity when carried out with chiral, nonracemic scaffolds. A subtle structural modification on the diene (replacement of an H by a trans-CH3 group) leads to a complete change of regiochemistry, which is discussed from a mechanistic point of view. The role of the eta3-coordinated TpMo(CO)2 moiety is also critical to the further functionalization of the [4 + 2] cycloadducts, as illustrated by the preparation of 20 variously functionalized 1-oxadecaline derivatives (>98% ee when carried out with high enantiopurity scaffolds).
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20
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Liu W, You F, Mocella CJ, Harman WD. A new approach to promoting sluggish Diels-Alder reactions: dihapto-coordination of the diene. J Am Chem Soc 2006; 128:1426-7. [PMID: 16448094 DOI: 10.1021/ja0553654] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The cycloaddition between 1,3-cyclohexadiene and various enones and enals (methyl vinyl ketone, ethyl vinyl ketone, methacrolien) is accomplished at room temperature in yields ranging from 51 to 68% without the use of Lewis acids, high pressures, or microwave reactors. This normally sluggish cyclization is accomplished by precoordination of the diene to a pi-basic molybdenum complex. The eta2-bound metal is thought to promote a Michael reaction between the uncoordinated portion of the diene and the enone, and the resulting enolate then closes to form the cycloalkene product. The organic cycloadduct is removed by oxidation with air or with silver triflate in nearly quantitative yield. For more sterically hindered enones (e.g., mesityl oxide) and for methyl acrylate, the desired outcome requires the use of BF3.OEt2, and yields are significantly lower (15-35%)
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Affiliation(s)
- Weijun Liu
- Department of Chemistry, University of Virginia, P.O. Box 400319, Charlottesville, Virginia, 22904-4319, USA
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21
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Zhang Y, Liebeskind LS. Organometallic enantiomeric scaffolding: organometallic chirons. Total synthesis of (-)-Bao Gong Teng A by a molybdenum-mediated [5 + 2] cycloaddition. J Am Chem Soc 2006; 128:465-72. [PMID: 16402833 DOI: 10.1021/ja055623x] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Bao Gong Teng A, an optically active tropane alkaloid with hypotensive and miotic activity isolated from the Chinese herb Erycibe obtusifolia Benth, was synthesized by an "organometallic chiron" strategy in which single enantiomers of TpMo(CO)(2)(eta(3)-pyridinyl) complexes are produced in quantity and then elaborated easily and efficiently to generate, after demetalation, highly enantiopure advanced synthetic intermediates possessing the tropane core.
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Affiliation(s)
- Yongqiang Zhang
- Sanford S. Atwood Chemistry Center, Emory University, Atlanta, Georgia 30322, USA
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23
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Fairlamb IJS, Lynam JM, Taylor IE, Whitwood AC. η1-Bound 2-Pyrone Complexes of Molybdenum and Iron: A Synthetic and Structural Study. Organometallics 2004. [DOI: 10.1021/om049523w] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ian J. S. Fairlamb
- Department of Chemistry, University of York, Heslington, York, U.K. YO10 5DD
| | - Jason M. Lynam
- Department of Chemistry, University of York, Heslington, York, U.K. YO10 5DD
| | - Ian E. Taylor
- Department of Chemistry, University of York, Heslington, York, U.K. YO10 5DD
| | - Adrian C. Whitwood
- Department of Chemistry, University of York, Heslington, York, U.K. YO10 5DD
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