对羟基苯甲酸乙酯合成的新方法

New Method of Synthesis for Ethyl p-Hydroxybenzoate

研究了以FeCl3·6H2O为固体催化剂,由既作反应物又作溶剂的95%乙醇和对羟基苯甲酸为原料合成对羟基苯甲酸乙酯,并讨论了催化的各种影响因素.实验表明,固体FeCl3·6H2O是合成对羟基苯甲酸乙酯的良好催化剂,最佳的反应条件为:醇酸摩尔比为2:1、催化剂与酸的摩尔比为0.12:1、反应时间为3h、回流温度.上述条件下,其收率高于77.5%,含量98%以上.

The preparation of ethye p hydroxybenzoate by the reaction of p hydroxybenzoic acid with 95% ethanel, which is both a reactant and solvent, by using FeCl 3·6H 2O as a catalyst has been studied. Various factors that effect the esterifaction have been discussed. results show that FeCl 3·6H 2O is an excellent catalyst for the synthesis of ethyl p hydroxybenzoate, and the optimum reaction conditions arethat the molar ratio of 95% ethanol to the acid is 2, the molar ratio of catalyst to the acid is 0.12, reflux temperature, and the reaction time is 3 hours. Under those conditions, the yield and purity of product are above 77.5% and 98% respectively.