Synthesis of N-Boc-α-amino Acids from Carbon Dioxide by Electrochemical Carboxylation of N-Boc-α-aminosulfones

Electrochemical reduction of N-Boc-α-aminosulfones in DMF using an undivided cell equipped with a Pt plate cathode and an Mg rod anode under atmospheric pressure of bubbling carbon dioxide through the solution under constant current conditions resulted in a reductive C–S bond cleavage with elimination of benzenesulfinate ion generating the corresponding anion species followed by fixation of carbon dioxide to give the corresponding N-Boc-α-amino acids in moderate to good yields.