Squaramide-Catalyzed Asymmetric Michael/Cyclization Cascade Reaction of Unsaturated Thiazolidinones and 3-Isothiocyanato Oxindoles: Synthesis of New Bispirocyclic Heterocycles
作者:Da-Ming Du、Yong-Xing Song
DOI:10.1055/s-0036-1591527
日期:2018.4
heterocycles bearing three contiguous chiral centers including two quaternary one via a Michael/cyclization cascadereaction 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