Rhodium-Catalyzed Direct Vinylene Annulation of 2-Aryloxazolines and Cascade Ring-Opening Using a Vinyl Selenone

Abstract Over the past two decades, transition-metal-catalyzed C–H activation and the subsequent oxidative cyclization with alkynes or their surrogates has emerged as a powerful synthetic tool for fused heteroaromatics. We report a Rh(III)-catalyzed annulation and ring-opening cascade reaction with 2-aryloxazolines. By utilizing a vinyl selenone as an oxidizing acetylene surrogate, the target three-component coupling products were obtained in high yields without using a stoichiometric amount of external oxidant.