Asymmetric Construction of Pyrrolidines Bearing a Trifluoromethylated Quaternary Stereogenic Center via Cu(I) -Catalyzed 1,3-Dipolar Cycloaddition of Azomethine Ylides with β-CF3 -β,β-Disubstituted Nitroalkenes

Li-Wei Tang; Bao-Jing Zhao; Li Dai; Man Zhang; Zhi-Ming Zhou

doi:10.1002/asia.201600941

Asymmetric Construction of Pyrrolidines Bearing a Trifluoromethylated Quaternary Stereogenic Center via Cu(I) -Catalyzed 1,3-Dipolar Cycloaddition of Azomethine Ylides with β-CF3 -β,β-Disubstituted Nitroalkenes

Chem Asian J. 2016 Sep 6;11(17):2470-7. doi: 10.1002/asia.201600941. Epub 2016 Aug 25.

Authors

Li-Wei Tang¹, Bao-Jing Zhao¹, Li Dai¹, Man Zhang¹, Zhi-Ming Zhou^{2

3}

Affiliations

¹ R&D Centre of Pharmaceuticals school of Chemical Engineering and the Environment, Beijing Institute of Technology, 5th Zhongguancun South Street, Haidian District, Beijing, China.
² R&D Centre of Pharmaceuticals school of Chemical Engineering and the Environment, Beijing Institute of Technology, 5th Zhongguancun South Street, Haidian District, Beijing, China. zzm@bit.edu.cn.
³ State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, 5th Zhongguancun South Street, Haidian District, Beijing, China. zzm@bit.edu.cn.

PMID: 27459478
DOI: 10.1002/asia.201600941

Abstract

A direct and convenient method has been developed for the synthesis of optically active pyrrolidines bearing a quaternary stereogenic center containing a CF3 group at the C-3 position of the pyrrolidine ring. The synthesis system, Cu(I) /Si-FOXAP-catalyzed exo-selective 1,3-dipolar cycloaddition of azomethine ylides with β-CF3 -β,β-disubstituted nitroalkenes, provides pyrrolidines with high diastereoselectivities (up to >98:2 d.r.) and excellent enantioselectivities (up to >99.9 ee) and performs well for a broad scope of substrates under mild conditions.

Keywords: copper; cycloaddition; ferrocenyloxazolinylphosphines; pyrrolidine; trifluoromethylation.