One-Pot Synthesis of Benzimidazo[2,1‑<i>b</i>]thiazoline Derivatives through an Addition/Cyclization/Oxidative Coupling Reaction

A novel and efficient approach to the synthesis of benzimidazo­[2,1-b]­thiazoline derivatives has been developed through an addition/cyclization/intramolecular oxidative C–H functionalization process. A variety of alkylene benzimidazo­[2,1-b] thiazolines were conveniently assembled from the reaction of aryl isothiocyanate and propargylic amine in the presence of Cu­(OAc)2 and PIFA at room temperature. The product could be further converted to substituted benzimidazo­[2,1-b]­thiazole derivatives.