甲酰化法制备3,4-二甲基苯甲醛  

Study of Synthesis of 3,4-Dimethylbenzaldehyde with Formylation Method

作　　者：张跃[1] 刘建武[1] 严生虎[1] 沈介发[1] 

机构地区：[1]江苏工业学院设计研究所,江苏常州213164

出　　处：《江苏工业学院学报》2007年第1期5-8,共4页Journal of Jiangsu Polytechnic University

摘　　要：叙述了3，4-二甲基苯甲醛国内外合成技术状况及各合成路线的对比，介绍了以邻二甲苯、CO、HCl为原料，以1，2-二氯乙烷为溶剂，Lewis酸为催化剂进行甲酰化反应的比较理想的合成方法和工艺流程，取物料配比为m（邻二甲苯）：m（AlCl3）：m（Cu2Cl2）：m（二氯乙烷）=1：1．25：0．15：2，反应时间控制在8h左右，反应温度在0～5℃，反应的单程转化率达到70％～80％，3，4-二甲基苯甲醛的含量≥98．5％。Synthesis condition and comparison of different routes for 3, 4-dimethyl benzaldehyde were described. The product was prepared by carbonylate reaction of O-xylene with CO and HCl, using Lewise acid as the catalyst, 1, 2-Chloroethane as the solvent, the influence factors on purity of final product were investigated in detail, sush as catalyst, reaction time and temperature. The synthetic route and reaction mechanism of 3, 4-dimethylbenzaldehyde were also introduced. After a series of stable experiment, the optimal conditions of synthesis were achieved, under following conditions： O-xylene/AlCl3/ Cu2Cl2/1, 2-CH2ClCH2Cl, 1 ： 1.25 ： 0.15 ： 2, reaction time was controlled about 8 hours, temperature： from 0 to 5 ℃, the single-pass-conversion can be increased to 80%. This method has some merits, including abundant raw materials, mild reaction conditions, much less of the content of isomer. At the same time, solvent and unreaction materials were recycled conveniently. After being refined, yield and purity of final product were quite high.

关 键 词：邻二甲苯 3 4-二甲基苯甲醛 甲酰化 合成 

分 类 号：TQ244.1[化学工程—有机化工]