溴法合成乙基香兰素的工艺改进

Synthesis of 3-Ethoxyl-4-Hydroxybenzaldehyde

采用正交实验的方法,在用对羟基苯甲醛溴化合成乙基香兰素的过程中对原料配比、反应温度及溶剂选择等影响产率的因素进行了研究,得出了提高产率的最佳条件。在溴化阶段用氯化溴代替溴素、用乙酸甲酯作助溶剂使一溴化物的产率提高了10%,达到91.3%;在乙氧基化步骤中用CuO作催化剂,用乙醇和DMF作反应溶剂使得最终产物的产率达到85.2%。

The method of synthetizing 3-Ethoxyl-4-Hydroxybenzaldehyde from 4-hydroxy-benzaldehyde was improved,which include using BrCl as the reagent of bromination,ethyl acetate as helpful solvent and so on.Factors affecting the pro cess were discussed and the optimized conditions were received as follows:using ethyl acetate as helpful solvent,reaction temperature 15℃,and p-HOC6H4CHO/BrCl (molar ratio)=1∶1.08.The product yield is 85.2%.