Total Synthesis of (±)-2-Debromohymenin via Gold-Catalyzed Intramolecular Alkyne Hydroarylation.

An intramolecular, gold-catalyzed alkyne hydroarylation results in the formation of the core pyrroloazepinone framework of the hymenin group of oroidin alkaloids. Elaboration of the cyclic adduct via C2-azidation, bromination of the pyrrole, and deprotection set the stage for global reduction with Mo(CO)6 resulting in the formation 2-debromohymenin.