3-氯-4-甲基苯胺合成研究

Study on the Synthesis of 3-Chloro-4-methylaniline

以3-氯-4-甲基硝基苯为原料，对常见还原工艺进行比较，确定了铂炭催化加氢是较佳的还原工艺路线。催化加氢最佳工艺条件是100g3-氯-4-甲基硝基苯原料，1g助催化剂A，1％铂炭催化剂加入量为1．0g，甲醇加入量在180—200mL，反应温度在85—90℃，反应氢压在3．0MPa。实验研究表明1％铂炭催化剂重复使用6次内具有很高的反应转化率和选择性。反应产物经精溜分离后得到的产品纯度在99．8％以上。

Using 3 - chloro - 4 - methyl - nitrobenzene as a raw material, the usual reduction processes were compared to determine that the process of catalytic hydrogenation was a better approach. The optimal conditions for the catalytic hydrogenation process were 100 g 3 - chloro -4 - methyl - nitrobenzene as raw material, 1 g catalyst promoter A, 1.0 g 1% Pt/C, 180 -200 mlmethanol, reaction temperature at 85 -90℃ and the hydrogen pressure at 3.0 MPa. The results showed that if recycling number of 1% Pt/C was less than 6 the conversion was quite high and the catalytic selectivity was superb. The purity of the product after rectifying process could reach to 99.8%.