Electrochemical α-hydroxylation of aryl ketones with methanol as the oxygen source†

Selective hydroxylation of Csp³–H bonds is challenging but highly valuable. This report describes electrochemical α-hydroxylation of aryl ketones under mild conditions without transition metal catalysts or oxygen gas; methanol serves as the oxygen source for preparing a series of compounds. Using deuterated methanol leads to α-deuterohydroxylation in a single step, thus offering a convenient isotope labeling approach. This method can be applied to effectively hydroxylate secondary Csp³–H bonds. Mechanistic investigations confirm methanol as the oxygen source, and scale-up experiments highlight the practical applicability of this reaction.