A photosensitized metal free approach to α‐ketoamides:sequential oxidative amidationdiketonization of terminal alkynes

Abstract

A novel transition metal‐free photosensitized protocol has been developed for the synthesis of α‐ketoamides via oxidative coupling of alkynes and amines in the presence of thiophenol under visible light irradiation and rose bengal dye. A series of alkynes with both electron‐donating and electron‐withdrawing groups were successfully employed for the synthesis of their corresponding α‐ketoamides. This reaction presents a benign visible light based milder synthetic methodology with broad functional‐group tolerance.