Synthesis 2011(17): 2767-2774  
DOI: 10.1055/s-0030-1260127
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Reaction of a Trifluoromethylated N-Monosubstituted Hydrazone with α,β-Ethenyl Ketones: A Novel Synthesis of Substituted Pyrazolidines and Pyrazolines

Haibo Xie, Jiangtao Zhu, Zixian Chen, Shan Li, Yongming Wu*
Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032, P. R. of China
Fax: +86(21)54925192; e-Mail: ymwu@sioc.ac.cn;
Further Information

Publication History

Received 12 May 2011
Publication Date:
19 July 2011 (online)

Abstract

We hereby describe an instance of diastereoselective trifluoromethanesulfonic acid catalyzed 1,3-dipolar cycloaddition of a trifluoromethylated azomethine imine with α,β-ethenyl ketones. Using two different reaction conditions, reaction of trifluoroacetaldehyde phenylhydrazone and chalcone derivatives gave polysubstituted pyrazolidines and pyrazolines derivatives with efficiency and high diastereoselectivity.