Concise Report
Palladium-Catalyzed Asymmetric [4+3]-Cyclization Reaction of Fused 1-Azadienes with Amino-trimethylenemethanes: Highly Stereoselective Construction of Chiral Fused Azepines
Prathibha Kumari,
Weiwei Liu,
Cheng-Jie Wang,
Jun Dai,
Mei-Xin Wang,
Qi-Qiong Yang,
Yu-Hua Deng,
Zhihui Shao,
Prathibha Kumari
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
These two authors contributed equally.Search for more papers by this authorWeiwei Liu
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
These two authors contributed equally.Search for more papers by this authorCheng-Jie Wang
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
Search for more papers by this authorJun Dai
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
Search for more papers by this authorMei-Xin Wang
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
Search for more papers by this authorQi-Qiong Yang
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
Search for more papers by this authorCorresponding Author
Yu-Hua Deng
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
E-mail: [email protected]; [email protected]Search for more papers by this authorCorresponding Author
Zhihui Shao
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
E-mail: [email protected]; [email protected]Search for more papers by this authorPrathibha Kumari,
Weiwei Liu,
Cheng-Jie Wang,
Jun Dai,
Mei-Xin Wang,
Qi-Qiong Yang,
Yu-Hua Deng,
Zhihui Shao,
Prathibha Kumari
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
These two authors contributed equally.Search for more papers by this authorWeiwei Liu
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
These two authors contributed equally.Search for more papers by this authorCheng-Jie Wang
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
Search for more papers by this authorJun Dai
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
Search for more papers by this authorMei-Xin Wang
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
Search for more papers by this authorQi-Qiong Yang
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
Search for more papers by this authorCorresponding Author
Yu-Hua Deng
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
E-mail: [email protected]; [email protected]Search for more papers by this authorCorresponding Author
Zhihui Shao
Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, Yunnan, 650091 China
E-mail: [email protected]; [email protected]Search for more papers by this authorSummary of main observation and conclusion
A Pd-catalyzed asymmetric aromative [4+3]-cyclization reaction of amino-trimethylenemethanes (TMM, 1,3-dipoles) with fused 1-azadienes has been developed. This method enables access to the synthetically importance and biologically active benzofuran fused azepines and indeno-azepines in excellent efficiency and stereoselectivity (up to 95% yield, 99% ee, >19 : 1 dr).
Supporting Information
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Appendix S1: Supplementary Material |
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- 13Examples on the catalytic asymmetric [3+2]-cyclization of TMM with olefins, please see: (a) Trost, B. M.; Stambuli, J. P.; Silverman, S. M.; Schwörer, U. Palladium-Catalyzed Asymmetric [3+2] Trimethylenemethane Cycloaddition Reactions. J. Am. Chem. Soc. 2006, 128, 13328–132329; (b) Trost, B. M.; Cramer, N.; Silverman, S. M. Enantioselective Construction of Spirocyclic Oxindolic Cyclopentanes by Palladium-Catalyzed Trimethylenemethane-[3+2]-Cycloaddition. J. Am. Chem. Soc. 2007, 129, 12396–12397; (c) Trost, B. M.; Silverman, S. M.; Stambuli, J. P. Development of an Asymmetric Trimethylenemethane Cycloaddition Reaction: Application in the Enantioselective Synthesis of Highly Substituted Carbocycles. J. Am. Chem. Soc. 2011, 133, 19483–19497; (d) Trost, B. M.; Bringley, D. A.; Seng, P. S. Enantioselective Palladium-Catalyzed [3+2] Cycloadditions of Trimethylenemethane with Nitroalkenes. Org. Lett. 2012, 14, 234–237; (e) Trost, B. M.; Bringley, D. A.; O'Keefe, B. M. Highly Substituted Enantioenriched Cyclopentane Derivatives by Palladium-Catalyzed [3+2] Trimethylenemethane Cycloadditions with Disubstituted Nitroalkenes. Org. Lett. 2013, 15, 5630–5633; (f) Trost, B. M.; Maruniak, A. Enantioselective Construction of Highly Substituted Vinylidenecylopentanes by Palladium-Catalyzed Asymmetric [3+2] Cycloaddition Reaction. Angew. Chem. Int. Ed. 2013, 52, 6262–6264; (g) Trost, B. M.; Zhang, L.; Lam, T. M. Synthesis of the Aminocyclitol Core of Jogyamycin via an Enantioselective Pd-Catalyzed Trimethylenemethane (TMM) Cycloaddition. Org. Lett. 2018, 20, 3938–3942; (h) Trost, B. M.; Zell, D.; Hohn, C.; Mata, G.; Marunaik, A. Enantio- and Diastereoselective Synthesis of Chiral Allenes by Palladium-Catalyzed Asymmetric [3+2] Cycloaddition Reactions. Angew. Chem. Int. Ed. 2018, 57, 12916–12920; (i) Trost, B. M.; Wang, Y. A Deprotonation Approach to the Unprecedented Amino-Trimethylenemethane Chemistry: Regio-, Diastereo-, and Enantioselective Synthesis of Complex Amino Cycles. Angew. Chem. Int. Ed. 2018, 57, 11025–11029; (j) Trost, B. M.; Jiao, Z.; Hung, C.-I. (Joey) Elaborating Complex Heteroaryl-Containing Cycles via Enantioselective Palladium-Catalyzed Cycloadditions. Angew. Chem. Int. Ed. 2019, 58, 15154–15158.
- 14Examples on the catalytic asymmetric [3+2]-cyclization of TMM with nitroarene, please see: Trost, B. M.; Ehmke, V.; O'Keefe, B. M.; Bringley, D. A. Palladium-Catalyzed Dearomative Trimethylene-methane Cycloaddition Reactions. J. Am. Chem. Soc. 2014, 136, 8213–8216.
- 15Examples on the catalytic asymmetric [3+2]-cyclization of TMM with carbonyl compounds: (a) Trost, B. M.; Mata, G. Enantioselective Palladium-Catalyzed [3+2] Cycloaddition of Trimethylenemethane and Fluorinated Ketones. Angew. Chem. Int. Ed. 2018, 57, 12333–12337; (b) Trost, B. M.; Bringley, D. A.; Silverman, S. M. Asymmetric Synthesis of Methylenetetrahydrofurans by Palladium-Catalyzed [3+2] Cycloaddition of Trimethylenemethane with Aldehydes: A Novel Ligand Design. J. Am. Chem. Soc. 2011, 133, 7664–7667.
- 16Examples on the catalytic asymmetric [3+2]-cyclization of TMM with imines: (a) Trost, B. M.; Silverman, S. M.; Stambuli, J. P. Palladium- Catalyzed Asymmetric [3+2] Cycloaddition of Trimethylenemethane with Imines. J. Am. Chem. Soc. 2007, 129, 12398–12399; (b) Trost, B. M.; Silverman, S. M. Enantioselective Construction of Highly Substituted Pyrrolidines by Palladium-Catalyzed Asymmetric [3+2] Cycloaddition of Trimethylenemethane with Ketimines. J. Am. Chem. Soc. 2010, 132, 8238–8240; (c) Trost, B. M.; Silverman, S. M. Enantioselective Construction of Pyrrolidines by Palladium-Catalyzed Asymmetric [3 + 2] Cycloaddition of Trimethylenemethane with Imines. J. Am. Chem. Soc. 2012, 134, 4941–4954; (d) Trost, B. M.; Lam, T. M.; Herage, M. A. Regio- and Enantioselective Synthesis of Pyrrolidines Bearing a Quaternary Center by Palladium-Catalyzed Asymmetric [3 + 2] Cycloaddition of Trimethylenemethanes. J. Am. Chem. Soc. 2013, 135, 2459–2461.
- 17Example on the catalytic symmetric [3+3]-cyclization of TMM: Shintani, R.; Hayash, T. Palladium-Catalyzed [3 + 3] Cycloaddition of Trimethylenemethane with Azomethine Imines. J. Am. Chem. Soc. 2006, 128, 6330–6331.
- 18Example on the catalytic symmetric [3+6]-cyclization of TMM: Trost, B. M.; McDougall, P. J.; Hartmann, O.; Wathen, P. T. Asymmetric Synthesis of Bicyclo[4.3.1]decadienes and Bicyclo[3.3.2]-decadienes via [6 + 3] Trimethylenemethane Cycloaddition with Tropones. J. Am. Chem. Soc. 2008, 130, 14960–14961.
- 19(a) Trost, B. M.; Zuo, Z. Highly Regio-, Diastereo-, and Enantioselective Synthesis of Tetrahydroazepines and Benzo[b]oxepines via Palladium-Catalyzed [4+3] Cycloaddition Reactions. Angew. Chem. Int. Ed. 2019, DOI: https://doi.org/10.1002/ange.201911537; (b) At almost the same time, Deng and Yang et al. disclosed their work: Liu, Y.-Z.; Wang, Z.; Huang, Z.; Zheng, X.; Yang, W.-L.; Deng, W.-P. Palladium-Catalyzed Asymmetric [4+3] Cyclization of Trimethylenemethane: Regio-, Diastereo-, and Enantioselective Construction of Benzofuro[3,2-b]azepine Skeletons. Angew. Chem. Int. Ed. 2019, DOI: https://doi.org/10.1002/anie.201909158.
- 20For more details, please see the Supporting Information.
- 21Crystallographic data for 3a has been deposited the Cambridge Crystallographic Data Centre (CCDC No. 1961388, 30% ellipsoid probability). Detailed Information can be found in the Supporting Information. The absolute conformations of all the other fused azepine products 3b—3m have been assigned accordingly.
