Pd(II)-Catalyzed Dehydrogenative Olefination of Vinylic C–H Bonds with Allylic Esters: General and Selective Access to Linear 1,3-Butadienes

This work demonstrates a general and efficient method to prepare conjugated dienes by Pd(II)-catalyzed direct olefination of unactivated alkenes with allylic esters and acrylates via vinylic C-H activation. Various aryl and heteroaryl alkenes as well as aliphatic alkenes all give the desired linear 1,3-butadienes with retention of the traditional leaving groups such as OAc and other carboxylic acid ester groups.