Formal gamma-C(sp3)–H Activation of Ketones via Microwave-Promoted and Iminyl-Radical-Mediated 1,5-Hydrogen Atom Transfer

Abstract

Microwave irradiation of O-phenyloximes triggers N–O homolysis and 1,5-hydrogen atom transfer (HAT), resulting in formal gamma-C–H functionalization of ketones after trapping of the radical intermediate and in situ imine hydrolysis. The Lewis acid InCl3∙H2O facilitated the HAT step, enabling functionalization of nonbenzylic 1° carbon atoms. Both C–O and C–C bond formation could be accomplished by this method.

Formal γ-C(sp3)–H Activation of Ketones via Microwave-Promoted and Iminyl-Radical-Mediated 1,5-Hydrogen Atom Transfer

“…The reactions are rapid and involve simple experimental protocols. Although more work is necessary for some yields to reach synthetically useful levels, we believe that the potential of this method justifies further investigation …”

“…Although more work is necessary for some yields to reach synthetically useful levels, we believe that the potential of this method justifies further investigation. 23 ■ EXPERIMENTAL SECTION General Details. Pyridine was dried by passage through a solvent drying system employing activated alumina cylinders.…”