电化学法一步合成邻、间、对氟苯甲酸

One-step Synthesis of o-,m- and p-Fluorobenzoic Acids by Electrochemical Method

以氟代氯苯为原料，用电化学法分别合成了邻（间、对）氟苯甲酸，考察了电极材料、反应温度、电流及反应物浓度对反应的影响。以镀锌不锈钢为阴极，镁为阳极，控制反应温度5℃左右，氟代氯苯初始浓度为0．50～0．70mol／L，邻、间、对氟苯甲酸产率分别为80％、75％、82％。现已完成电解槽容积为50mL的小试及15L的扩试，目前100L的中试正在进行中。

Electrochemical carboxylation of various fluorophenyl halides （ 0.50 - 0.70 mol/L） were carried out at 5 ℃ in an undivided cell, with N, N-dimethylformamide （DMF） as the solvent, magnesium as the dissolving anode and galvanized stainless steel as the cathode, to give o-, m- and p- fiuorobenzoic acids in 80% ,75% and 82% yields respectively. Experiments of 50 mL-scale and 15 L- scale have been done,and 100 L pilot synthesis is in progress.