Pd-Catalyzed Olefination of Furans and Thiophenes with Allyl Esters

A direct Pd(II)-catalyzed olefination of furans and thiophenes with allyl esters is demonstrated. Under the typical conditions, the dehydrogenative Fleck coupling reactions of heteroarenes with allylic esters proceeded via a beta-H elimination rather than a beta-OAc elimination to give the corresponding gamma-substituted allylic esters.