Electrochemical Decyanative Carboxylation of Cyanoaromatics with CO2 Leading to Aryl Carboxylic Acids

We present an electroreductive C-C bond activation strategy for decyanative carboxylation of cyano(hetero)aromatics with CO₂ to access aryl carboxylic acids. This strategy is characterized with the mild, transition-metal-free conditions, a high chemo-/regioselectivity, a broad substrate scope, and a good functional group tolerance, offering a general route to the synthesis of aryl carboxylic acids by selective functionalization of the CN functionality rather than the previously reported reactive functionalities like halo groups. Mechanistic experiments indicate that the reaction executes dual single electron reduction steps to allow direct nucleophilic addition with CO₂.