Control of Chemo-, Regio-, and Stereoselectivities in Ligand-Free Pd-Catalyzed Oxidative Heck Reactions of Arylboronic Acids or Alkenylboronate with Allyl Esters

A ligand-free Pd-catalyzed highly selective oxidative Heck reaction of organoboronic acids with allyl esters was developed. beta-H elimination is highly chemoselectively controlled, leading to gamma-substituted allyl esters, which is contrary to the traditional Heck-type reactions of allyl esters. Moreover, the regio- and stereoselectivities are also high due to the chelation between O and Pd atoms.