Photoinduced Nitrogen-to-Alkyl Radical Relay Heck Reaction of o-Alkylbenzamides with Vinyl Arenes by Palladium Catalysis

Here,a palladium-catalyzed photoinduced N-to-alkyl radical relayHeck reaction of o-alkylbenzamides at benzylic siteswith vinyl arenes is described. The reaction employs neither exogeneousphotosensitizers nor external oxidants. It is proposed to proceedvia a N-to-alkyl hybrid palladium-radical mechanism which occursunder mild conditions that are compatible with a wide range of functionalgroups. The products are easily transformed to azepinone derivatives,which are prevalent in pharmaceuticals and natural products.