Anodic Synthesis of Organic Carbonates

Carbonic acid esters (carbonates) are produced by electrolysis of carbon monoxide and the corresponding alcohol in the presence of a halide electrolyte. The halide electrolyte plays a catalytic role in carbonate formation. The efficiency for the process depends, among other variables, on the starting alcohol. Both mono and 1,2‐dihydric aliphatic alcohols form carbonates in high yields. Under our electrolytic conditions, without optimization, dimethyl carbonate from methanol and ethylene carbonate from ethylene glycol were formed with 80 and 45% current efficiencies, respectively. One mole of hydrogen is liberated per mole of carbonate. Organic carbonates represent a class of important industrial solvents. They are commercially produced via employment of phosgene; is formed as a by‐product. The electrochemical process obviates the use of phosgene and eliminates the hydrochloric acid disposal problem.