Unveiling Alternate Electrode Electrolysis in Electro-Photochemical and Electro-Organic Syntheses

Electro-photochemical organic synthesis is a rapidly growing field. Recently, technological advancement has contributed significantly to improve electro- and photolytic organic transformations in terms of energy efficiency and productivity. Herein, we have introduced alternating electrode electrolysis|alternate electrode electrolysis (AEE), a new technique in electrosynthesis which in combination with blue LED demonstrated an interesting three-component reaction with aryl diazoesters, 1,4-quinones, and acetone to synthesize ketal-functionalized 1,4-quinones. The AEE setup consists of two pairs of cathode-anode compared to the conventional setup of one pair. Each pair would be polarized or in a resting stage with a preset interval of choice. This would maintain a continuous potential resulting in maximum current and would facilitate the mass transport, thereby increasing the overall efficiency of the reaction. AEE offers the efficient utilization of photochemically generated carbenes. We extended AEE applications in paired photoelectrolysis reactions for the late-stage functionalization of bioactive molecules and pharmaceutical agents. As an application of AEE in electrosynthesis (without light), we demonstrated the efficient hydroxylation of fluorinated benzene and the reduction of benzonitrile to benzyl amine. The amalgamation of AEE with blue LED contributes to sustainability, and we believe that it holds great promise in the field of electro-photochemical organic synthesis.