磺酸树脂催化合成对叔丁基苯甲酸甲酯的研究

Efficient sulfonic acid resin catalysts for synthesis of methyl 4-tert-butylbenzoate

对叔丁基苯甲酸甲酯(MPTBBA)的传统催化合成方法大多具有难以分离、易腐蚀设备的问题。采用磺酸型阳离子交换树脂催化剂,系统研究了催化合成MPTBBA过程中磺酸树脂种类、反应温度、催化剂用量及原料配比对催化性能的影响。采用D001磺酸树脂为催化剂,在反应温度为120℃、甲醇与对叔丁基苯甲酸(PTBBA)摩尔比为8∶1、催化剂质量分数为10%的条件下,反应3 h PTBBA的转化率即可达到90%。对磺酸树脂催化剂的热稳定性及表面酸性的表征结果发现,催化剂具有较好的热稳定性,其催化活性与酸量有关,酸量越高磺酸树脂催化剂活性越高。该催化剂重复循环利用性能好、与产物易分离,具有广泛的工业应用前景。

Methyl 4-tert-butylbenzoate(MPTBBA)is an important intermediate in the pharmaceutical industry and organic synthesis applications.But most of the traditional synthesis methods for MPTBBA have the shortcomings in separation and corrosion.Sulfonic acid type ion exchange resin catalyst is used in catalytic synthesis of MPTBBA,the effects of resin types,reaction temperature,catalyst dosage and raw materials ratio on the catalytic performance of the catalyst are investigated.Among all catalysts,D001 sulfonic acid resin catalyst exhibits the best catalytic performance.The conversion rate of p-tert-butylbenzoic acid(PTBBA)can reach 90%after 3 h by using D001 sulfonic acid resin as catalyst when reaction temperature remains at 120℃,the molar ratio of methanol to PTBBA is 8∶1 and catalyst dosage is 10 wt.%.It is found through characterization that sulfonic acid resin catalysts possesses good thermal stability in the reaction,and their catalytic performance depends on their acid amount.The catalyst with higher acid amount exhibits better catalytic performance.The sulfonic acid resin catalysts can be separated from the products conveniently and maintains stable high catalytic performance after 6 cycles of use,which shows a promising prospect in industrial application of MPTBBA synthesis.