对羟基苯丙烯酸的改进合成

Improved synthesis of the 3-(4-hydroxyphenyl)acrylic acid

为研究以对羟基苯甲醛和丙二酸为原料,经Knoevena-gel缩合反应合成对羟基苯丙烯酸的实验条件,通过对比实验的方法,考察了溶剂、催化剂、反应温度及反应物摩尔比对反应的影响.确定了最佳实验条件:以1,4-二氧六环为溶剂,吡啶和哌啶为催化剂,对羟基苯甲醛和丙二酸摩尔比为1∶3.结果表明,与使用吡啶为溶剂的传统方法相比,该方法收率由83%提高至88%,且溶剂1,4-二氧六环比吡啶更加经济和环保.并通过核磁谱图对合成化合物的结构进行了表征.

The effects of solvent, catalyst, temperature and the ratio of starting materials on reaction were investigated by corn parison method to study the synthesis of 3-（4-Hydroxyphenyl） acrylic acid by the Knoevenagel condensation of 4-hydroxy benzaldehyde with malonic acid. The optimum experimental conditions for synthesising 3-（4-Hydroxyphenyl）acrylic acid are as follows： 1,4-dioxane is used as solvent, pyridine and piperidine as catalyst, and the molar ratio of 4-hydroxy henzaldehyde to malonic acid is 1：3. Compared with traditional method using pyridine as solvent, the proposed method makes the yield increases from 83% to 88% and the 1,4-dioxane is cheaper and more environment-friendly than pyridine. The structure of the product is characterized by NMR.