Synthesis 2018; 50(07): 1535-1545
DOI: 10.1055/s-0036-1591527
paper
© Georg Thieme Verlag Stuttgart · New York

Squaramide-Catalyzed Asymmetric Michael/Cyclization Cascade Reaction of Unsaturated Thiazolidinones and 3-Isothiocyanato Oxindoles: Synthesis of New Bispirocyclic Heterocycles

Yong-Xing Song
School of Chemistry and Chemical Engineering, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing 100081, P. R. of China   Email: dudm@bit.edu.cn
,
School of Chemistry and Chemical Engineering, Beijing Institute of Technology, 5 South Zhongguancun Street, Beijing 100081, P. R. of China   Email: dudm@bit.edu.cn
› Author Affiliations
The authors are grateful for financial support from the National Natural­ Science Foundation of China (grant number 21272024).
Further Information

Publication History

Received: 06 November 2017

Accepted after revision: 08 December 2017

Publication Date:
22 January 2018 (online)


Abstract

A highly efficient method for the construction of oxindole-pyrrolidone-thiazolidinone bispirocyclic heterocycles bearing three contiguous chiral centers including two quaternary one via a Michael/cyclization cascade reaction has been developed. Using bifunctional cinchona-derived squaramide as catalyst, the reactions of 3-isothio­cyanato oxindoles with unsaturated thiazolidinone derivatives proceeded smoothly under mild reaction conditions to afford a series of complex chiral oxindole-pyrrolidone-thiazolidinone bispirocyclic heterocycles in high yields (up to 99%) with excellent diastereo- and enantioselectivities (up to >99:1 dr, >99% ee).

Supporting Information