苯甲醛直接氯化法合成间氯苯甲醛

以苯甲醛为原料直接氯化合成间氯苯甲醛,通过对几种可能的催化剂进行比较,选择了无水三氯化铝作为该氯化反应的催化剂;用单因素方法和正交实验考察了原料液浓度、催化剂用量、反应温度和反应时间对氯化反应的影响,得到了氯化反应优惠条件:苯甲醛1 33mol/L,无水三氯化铝1 70mol/L,反应时间30min,反应温度50℃。苯甲醛的转化率≥90%,间氯苯甲醛的收率≥79%,选择性为88%,氯化产品中基本无同分异构体。

Studies on the Synthesis of m-Chlorobenzaldehyde from Benzaldehyde by Direct Chlorination

The synthesis method of m chlorobenzaldehyde from benzaldehyde by direct chlorination was studied. Anhydrous aluminium was picked out as the best catalyst from many kinds of catalysts. By parameters and orthogonal test, the effects of the concentration of raw material, the catalyst, reaction temperature, and reaction time was investigated. The optimized conditions for reaction were obtained as follows: benzaldehyde 1.33 mol·L -1 , anhydrous aluminium 1.70 mol·L -1 , reaction time 30min, reaction temperature 50℃. Under the optimized conditions, the conversion of benzaldehyde is over 90%. The overall yield of m-chlorobenzaldehyde is 79% with 88% selectivity, and there almost is no structural isomer as by products.