Abstract: We have prepared covalently modified graphite electrodes(CelValM)that bind L-valine methyl ester to their surface via amide bonds,thereby providing a stable,chiral interfacial region for the reduction of acetophenone.The optical yield(o.y.)and chemical yield (c.y.)of S(-)-1-phenylethanol were measured as a function of CelValM cathode potential, current density,amount of electricity passed,substrate concentration,pH,and the number of repeated use of electrodes.The highest o.y.was 15.8%.The characteristics and kinetic parameters of electrode processes were determined by potentiodynamic method and rotating disk electrode.A possible mechanism of the asymmetric electroreduction of acetophenone was forwarded.

Key words: L-valine methyl ester, modified electrode, asymmetric reduction, acetophenone