Electroreduction of Aromatic Carboxylic Derivatives to Aldehydes

The selective electroreduction of aromatic carboxylic acid derivatives is widely recognized as a significant transformation in organic chemistry. However, achieving both selectivity and generality across a broad range of carboxylic acid derivatives remains challenging. Building on recent advances in selective electroreduction, we report an electrochemical method for the selective reduction of diverse aromatic carboxylic acids and their derivatives to aldehydes via a silicon-assisted electroreduction strategy with alternating current (AC) electrolysis. This protocol exhibits high chemoselectivity, a wide substrate scope, and good functional group compatibility under mild conditions, thus enabling the efficient synthesis of a diverse range of aromatic aldehydes. Mechanistic studies suggest the involvement of a ketyl radical intermediate, highlighting the critical role of silicon moieties in the formation of final aldehyde products.