3-甲氧基二苯胺合成工艺改进及条件优化

Study of Synthesis of 3-Methoxydiphenylamine

3-甲氧基二苯胺是一种重要的精细化学品,但目前工业化生产还存在收率低、纯度不高等问题。对现有3-甲氧基二苯胺合成的多条工艺路线作了分析和比较,确定了以苯胺和间苯二酚为起始原料分两步合成该产品的工艺路线,并且对该工艺进行了改进,由原来的高压法改为常压法合成3-羟基二苯胺中间产品,再经硫酸二甲酯的甲基化反应得到最终产品;并对影响两步反应的主要因素进行了考察,通过正交实验法筛选出最佳工艺条件,最终可使产品收率高达76％,纯度也达98％以上。

3 - Methoxydiphenylamine is an important fine chemical. But the product's yield in the industrialized production is low and the purity is not high. After the analysis and compare of several processes, a suitable process that was found was to use aniline and resorcinol as initiative material through two steps to synthesis 3 - methoxydiphenylamine. The process was improved from original high pressure method into normal pressure method to synthesis 3 - hydroxyldiphenylamine, then via the reaction with (CH3)2SO4 to synthesis 3 -methoxydiphenylamine. Various factors which influence the reaction were investigated and optimum reaction conditions were selected by orthogonal design. Under the optimized conditions, the yield was above 76% and the purity was over 98%.