微波法强酸性树脂催化合成对羟基苯甲酸酯

Synthesis of alkyl p-hydroxybenzoate by using strong acidic cationic exchange resin as catalyst under microwave irradiation

采用强酸性阳离子交换树脂为催化剂,以对羟基苯甲酸和脂肪醇为原料,在微波辐射下合成了8种C2～8烷基对羟基苯甲酸酯。探讨了微波功率、微波辐射时间、催化剂用量、醇酸摩尔比等对合成对羟基苯甲酸丁酯产率的影响。结果表明,微波功率320 W、微波辐射30 min、醇酸摩尔比8∶1、强酸性阳离子交换树脂0.6 g,在无带水剂存在下,对羟基苯甲酸丁酯的产率可达90.3%。同时考察了催化剂的重复使用性。

Eight kinds of C2-8 alkyl p -hydroxybenzoate were synthesized by using p -hydroxybenzoie acid and aliphatic alcohols as starting materials as well as strong acidic cationic exchange resin as catalyst under microwave irradiation. The effects of microwave power, microwave irradiation time, dosage of the catalyst and molar ratio of butyl alcohol to p - hydroxybenzoic acid on the yield of butyl p - hydroxybenzoate were investigated. Results showed that the yield of butyl p - hydroxybenzoate achieves 90. 3 % under the condition of power of microwave 320 W, microwave irradiation time 30 min, molar ratio of alcohol to acid 8 ： 1, dosage of strong acidic cationic exchange resin 0. 6 g, and in the absence of water stripping agent. The performance of reused catalyst was examined.