Cu-catalyzed three-component aminodifluoroalkylative cyclization of styrenes: Access to ,-difluoro--lactams

We describe a simple, practical copper-catalyzed intermolecular three-component aminodifluoroalkylative cyclization reaction of alkenes with ethyl bromodifluoroacetate and anilines to alpha,alpha-difluoro-gamma-lactams in one step. Contrary to related carboamination reactions, in addition to electron-rich vinylarenes, electron-neutral and electron-poor styrenes can also be functionalized. Preliminary mechanistic studies demonstrate the involvement of carbon-centered radical, while ruling out the possibility of bromodifluoroacetamide intermediate.