Cobalta-Electrocatalyzed C-H Allylation with Unactivated Alkenes

Versatile and robust cobalt catalysis enabled the electrochemical C-H allylation with nonactivated alkenes. In contrast to precious palladium, rhodium, iridium, and ruthenium catalysts that are limited to electronically activated styrenes and acrylates, we herein disclose cobalt-catalyzed electro-oxidative C-H allylations with nonactivated alkenes. Thus, allylated benzamides were obtained with high levels of chemoselectivity, positional selectivity, and regioselectivity in the biomass-derived solvent γ-valerolactone. Detailed mechanistic studies provided strong support for a base-assisted internal electrophilic-type substitution mechanism for the key C-H activation step. The cobaltaelectro-catalysis overall achieved resource-economy by avoiding the use of stoichiometric chemical oxidants, with H2 as the only byproduct.