Electrocarboxylation of acetophenone to 2-hydroxy-2phenylpropionic acid in the presence of CO2

Electrocarboxylation of acetophenone with CO2 to obtain 2-hydroxy-2-phenylpropionic acid was carried out in acetonitrile solution containing 0.1 mol center dot L-1 tetraethylammonium bromide. Influences of the nature of the electrodes, the working potential, the passed charge and the concentration of acetophenone on the electrocarboxylation were studied. After optimizing the synthetic parameters, the maximal isolated yield reached 73.0% on Mg-stainless steel couple electrodes under potentiostatic electrolysis until 2.2 F center dot mol(-1) of charge was passed at 25 V. The reduction of acetophenone was studied by cyclic voltammetry and the mechanism has been proposed on the basis of the results.