Towards the electroreduction of very weak acids

Abstract

In order to improve the understanding of the synthesis of electrogenerated bases (EGB), the electrochemical reduction of two weak acids, 2-pyrrolidone (pKa(DMSO) = 24.2 and hexamethyldisilazane (HMDS, pKa(DMSO) = 26), has been compared in DME+HMPA+Et4NBF4 solution using the sacrificial magnesium anode method in an undivided cell under constant current. Both acids are reduced at transition metal cathodes to form dihydrogen and their conjugate base (as evidenced by their deprotonation abilities) whereas no gas evolution is observed at non-catalytic surfaces such as glassy carbon. Kinetic studies of dihydrogen evolution at Pt, stainless steel, Fe and Ni, throughout the electrolysis showed diffe..