Enantioselective cyclization reactions involving 3-isothiocyanato oxindoles: synthesis of spirocycles

Abstract

Recently, 3-isothiocyanato oxindoles have been used in various asymmetric cascade cyclization reactions for the synthesis of biologically important spirocyclic compounds. As a powerful and versatile ambiphilic synthon, 3-isothiocyanato oxindoles react effectively with diverse electron-deficient unsaturated bonds through Michael addition/cyclization reactions under organocatalysis or metal catalysis systems. This review highlights catalytic enantioselective cyclization reaction of 3-isothiocyanato oxindoles since 2011, and discusses their mechanistic insights.