Cobalt-Catalyzed Regioselective Direct C-4 Alkenylation of 3-Acetylindole with Michael Acceptors Using a Weakly Coordinating Functional Group

Herein, we disclosed the first report on the selective C(4)-H functionalization of 3-acetylindole derivatives using first-row transition metal cobalt where an acetyl group is acting as a weakly coordinating directing group. Selective C(4)-H functionalization has been achieved using diverse Michael acceptors (acrylate and maleimide) simply by switching the additive from copper acetate to silver carbonate. Further the formation of acobaltacycle intermediate was also detected through HRMS for mechanistic insight.