取代邻硝基苯胺的还原工艺改进

对取代邻硝基苯胺的还原方法进行了改进 :采用 Raney- Ni催化下水合肼还原 ,制得的取代邻苯二胺与乙基黄原酸钾环缩合生成取代巯基苯并咪唑 ,总收率达 84%～ 92 % ;比较了几种常见的还原剂对 2 -硝基 - 4-甲氧基苯胺的还原情况 ,以及催化剂用量与反应温度对产物收率的影响。可以看出 :用水合肼还原取代邻硝基苯胺是一种行之有效的方法。

An Improvement on the Reduction of Substituted o-Nitroaniline

A new reduction method of substituted o nitroaniline is reported. The titled compound was reduced by hydrazine hydrate in the presence of Raney Ni to give substituted 1,2 benzenediamine and then substituted 2 benzimidazolethiol was synthesized via cyclocondensation reaction of substituted 1,2 benzenediamine with potassium ethyl xanthate. The overall yield was 84%~92%. In addition, the reduction of N (2 nitro 4 methoxy) phenylamine in the presence of several different reductants was compared, showing that the hydrazine hydrate process was simple and suitable for industrialization.