Copper-catalyzed difluoromethylation of propargylamide-substituted indoles: synthesis of mono- and bis-difluoromethylated indoloazepinone derivatives

Abstract

A novel copper-catalyzed difluoromethylation of 2- or 3-propargylamide-substituted indoles with ICF₂CO₂Et via a radical cascade cyclization process is described. A wide substrate scope is compatible with the reaction conditions to synthesize mono- and bis-difluoromethylated indoloazepinone derivatives, which contain a seven-membered ring.