Aryl-to-alkyl radical relay Heck reaction of amides with vinyl arenes

Abstract

A palladium-catalyzed aryl-to-alkyl radical relay Heck reaction of amides at α-C(sp³)-H sites with vinyl arenes is described. This process displays a broad substrate scope with respect to both amide and alkene components and provides access to a diverse class of more complex molecules. The reaction is proposed to proceed via a hybrid palladium-radical mechanism. The core of the strategy is that the fast oxidative addition of aryl iodide and fast 1,5-HAT overcome the slow oxidative addition of alkyl halides, and the photoexcitation effect suppresses the undesired β-H elimination. It is anticipated that this approach would inspire the discovery of new palladium-catalyzed alkyl-Heck methods.