离子液体催化邻苯二酚与叔丁醇烷基化反应

SO3H-FUNCTIONALIZED IONIC LIQUIDS FOR SELECTIVE ALKYLATION OF CATECHOL WITH tert-BUTANOL

以廉价的烷基胺为原料合成了SO3H-功能化离子液体(IL),并采用NMR、ESI-MS、TG-DTG等手段对其结构及物性进行表征。将该离子液体作为催化剂,考察反应条件对离子液体催化邻苯二酚叔丁醇(TBA)烷基化反应性能的影响,以及离子液体的重复使用性,比较了离子液体与常规酸催化剂催化该烷基化反应性能的差别。结果表明,在反应温度150℃、反应时间3 h、n(邻苯二酚)∶n(TBA)∶n(IL)为2∶1∶0.1的优化条件下,邻苯二酚的转化率、4-叔丁基邻苯二酚(4-TBC)的选择性分别可达41.5%和97.1%,与液体酸的催化效果接近。根据实验结果和模拟计算推测了可能的反应机理。

SO3H-functionalized ionic liquids （IL） were synthesized by using tri-alkylamine and 1,4-butanesultone as the sources. The structures and physical properties of ILs were characterized by NMR, ESI-MS and TG-DTG. Their catalytic performances in the alkylation of eateehol with tert-butyl alcohol （TBA） were investigated. The influences of reaction temperature, reaction time, reactant ratio, the amount and the recycle times of IL on the catalytic performance of IL in the tert-butylation of catechol were studied. Meanwhile, the catalytic performance of IL was compared with that of conventional liquid acids and solid acids. The results indicated that under optimized reaction conditions of 150℃, 3 h, n（Catechol） ： n（TBA） ： n（IL） was 2 ： 1 ： 0.1, the conversion of catechol and the selectivity of 4-TBC were 41.5% and 97.1% respectively. The SO3 H-functionlized ionic liquid exhibited high catalytic activity in the alkylation of catechol similar to liquid acid. The possible mechanism for this reaction system was reaction results and the simulation calculated results.