2,6-二氯苯甲醛的合成

Synthesis of 2,6-Dichlorobenzaldehyde

本文详细阐述了以6-氯邻硝基甲苯为原料经氯化、水解、提纯等过程来制备2,6-二氯苯甲醛的方法,对不同催化剂的催化效果进行了详细探讨,系统研究了合成2,6-二氯苯甲醛的优化条件,找到了具有良好催化效果的氯化催化剂,优化条件为:(1)在催化剂Sca-1的催化下,催化剂加入量为6-氯邻硝基甲苯的千分之一,氯化温度为180℃-185℃;(2)水解以90％的硫酸为佳,水解温度80℃,酸的加入量为:二氯苄(w):硫酸(w)=1:1.6;(3)蒸气提纯的温度应控制在150℃-180℃,重结晶溶剂为120号石油醚,总收率为61％。

2,6-Dichlorobenzaldehyde was prepared from 6-chloro-2-nitrotoluene by chlorination and hydrolysis, then purified. Optimum conditions were: (1) chlorination catalyzed by Sca-1 at 1 ppt of 6-chloro-2-nitrotoluene, at 180-185℃ (2) hydrolysis with a sulfuric acid concentration of 90%, at 80℃ and a feed weight ratio of w( α,α, 2,6-tetra-chlorotoluene):w(90%H2SO4)=1: 1 .6; and (3) steam distillation at 150-180℃ to 180℃ with 120# petroleum ether as the solvent for recrystallization. The overall yield was 61%.