L-缬氨酸甲酯修饰石墨电极不对称还原苯乙酮

Asymmetric Reduction of Acetophenone Using L-Valine Methyl Ester Modified Graphite Electrode

电化学不对称还原与普通化学方法相比有反应条件温和、易于控制、手性试剂用量小、产物纯、易于分离等优点,受到人们重视.1975年 Miller 等将 L-苯丙氨酸甲酯通过酰胺键修饰到石墨电极表面,用于还原4-乙酰吡啶和苯甲酰甲酸乙酯,均获旋光性产物,而

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 in- terfacial 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.