壳聚糖负载氯化铜催化苯甲醛乙二醇缩醛

Catalytic Synthesis of Benzaldehyde Glycol Acetal by Chitosan Doped with CuCl_2 as Catalysts

以壳聚糖和金属氯化物为原料制备了多种催化剂,并将其应用到苯甲醛乙二醇的缩醛反应.考察醇醛的物质的量比、反应时间、催化剂用量、带水剂的量等因素对反应的影响.实验结果表明,壳聚糖负载CuCl2作为催化剂时效果最好.通过响应面分析法得出该缩醛反应的最佳工艺条件为:n(醇)∶n(醛)=1.4∶1,催化剂用量为0.25g,反应时间3h,带水剂用量12.5mL,此条件下缩醛反应的产率90.0%,结果与模型预测值基本相符.

Different catalysts were prepared with chitosan and metalchloride as the raw materials,and applied to the acetalization of benzaldehyde glycol acetal.The effects of various reaction conditions,including aldehyde/alcohol molar ratio,reaction time,amount of catalysts and amount of water carrying agent were investigated.It was shown that chitosan doped with CuCl2 had the best catalytic performance,and the optimal conditions for esterification catalyzed by chitosan doped with CuCl2 were as follows:n(glycol)∶n(benzaldehyde)=1.4∶1,the amount of catalyst was 0.25 g,the reaction time was 3 h and the amount of water-carrying agent was 12.5 mL.Under these conditions,the best yield of acetalization reaction reached 90.0%,in basic agreement with the values predicted by the mathematical model.