Aerobic Palladium(II)-Catalyzed Dehydrogenation of Cyclohexene-1-carbonyl Indole Amides: An Indole-Directed Aromatization

Abstract

A palladium­(II)-catalyzed oxidative dehydrogenation of cyclohexene-1-carbonyl indole amides yielding the corresponding benzoylindoles is reported. The new aromatization is also applied to functionalized indoles such as tryptamine and tryptophan. The tethered indole is likely acting as a directing group for allylic C–H bond activation, and there is evidence for a mechanism proceeding through 1,3-diene formation followed by aromatization