Transition-Metal-Catalyzed Rapid Synthesis of Imidazo2,1-bthiazoles: Access to Aza-Fused Heterocycles via Aerobic Oxidative Coupling of 2-Aminothiazoles and Acetophenones

Abstract We report an efficient synthesis of 6-substituted imidazo2,1-bthiazoles from 2-aminothiazoles and acetophenones through intramolecular cyclization of in situ generated thiazolium ylides. This one-pot cascade process efficiently forms two C–N bonds and is facilitated by both Cu(OTf)2/KI and FeCl3/ZnI2 systems. The method utilizes commercially available starting materials and features mild reaction conditions, tolerance to different functional groups, and ease of operation. The synthetic applicability has further been demonstrated through post-modification of imidazo2,1-bthiazole analogues.