Water-Enhanced Electrochemical Hydrogenolysis of Aryl C–O Bonds

Abstract

Phenolic compounds are naturally abundant and easily derived, yet the cleavage of aryl C–O bonds typically relies on specific methods, especially those involving transition metal catalysts. In this study, we present a user-friendly and sustainable electrochemical approach for aryl C–O bond cleavage and hydrogenation. Salient features of this method include the use of an undivided cell, inexpensive dimethylformamide as a hydrogen source, a broad substrate scope, and practical derivatizations. A key factor in the success of this approach is the addition of water, which acts as a decomposing agent for the iminium intermediate, potentially competing with the substrate in cathodic reduction. Mechanistic studies elucidate the reaction cycle, with particular emphasis on the one-electron reduction process and the role of bromide.