Electrochemical carboxylation of cinnamate esters in MeCN

Electrochemical carboxylation of cinnamate esters has been carried out by cathodic reduction of CC bond in an undivided cell equipped with Mg sacrificial anode and using MeCN saturated with CO₂ as solvent. The yields and the ratio of mono- and dicarboxylic acids are strongly affected by various factors: cathodic material, current, charge, and temperature. The highest yield (78.9%) was obtained starting from ethyl cinnamate. Cyclic voltammograms have been measured and reaction pathways have been proposed.