Electrochemically Chloride Anion-Mediated Dialkoxylation of Diazo Compounds with Alcohols Enabling Synthesis of Ketals.

An electrochemical carbene radical cation-initiated dialkoxylation reaction of diazo compounds has been developed, which affords ketals as products in up to a 98% yield. The use of chloride salts enables the generation of a chlorinated intermediate that serves as the key catalytically active species in this process. Mechanistic data reveal that the reaction proceeds via anodic oxidation of diazo, coupling with chloride anion, coupling with alcohol, and substitution by alcohol to form the target ketals. Furthermore, broad substrate, mild reaction conditions, and scalability demonstrate that this process has easy access to ketals.