Cobalta-Electrocatalyzed C–H Allylation with Unactivated Alkenes
Uttam Dhawa, Cong Tian, Weizhao Li, Lutz Ackermann
Abstract
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.