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
Organocatalytic Cyclization of COS and Propargylic Derivatives to Value‐Added Heterocyclic Compounds
作者:Hui Zhou、Rui Zhang、Sen Mu、Hui Zhang、Xiao‐Bing Lu
DOI:10.1002/cctc.201900490
日期:2019.12.5
and 1,3‐thiazolidine‐2,4‐diones derivatives in a highly chemo‐ and stereoselective manner. The isotope labeling and stoichiometric experiments suggested the LB‐COS adducts preferentially mediated basic ionic pair mechanism. Furthermore, the practical application of this methodology was highlighted by the highlyefficientsynthesis of rosiglitazone using COS as sulfur source.