alpha-Aminoxy-Acid-Auxiliary-Enabled Intermolecular Radical gamma-C(sp(3))-H Functionalization of Ketones

A method for site-specific intermolecular gamma-C(sp(3))-H functionalization of ketones has been developed using an -aminoxy acid auxiliary applying photoredox catalysis. Regioselective activation of an inert C-H bond is achieved by 1,5-hydrogen atom abstraction by an oxidatively generated iminyl radical. Tertiary and secondary C-radicals thus formed at the gamma-position of the imine functionality undergo radical conjugate addition to various Michael acceptors to provide, after reduction and imine hydrolysis, the corresponding gamma-functionalized ketones.