制备、表征了酸功能化离子液体1-(3-磺酸)丙基-3-甲基咪唑磷酸二氢盐((HSO,-pmim)H2PO4),并用于催化合成乙酸松油酯的反应研究,考察了反应时间、反应温度、原料配比、催化荆用量等因素对反应的影响。在松油醇5.1g、n(松油醇):n(乙酸酐)1:1.5、离子液体1.5g、反应温度40℃、反应时间8h的工艺条件下,松油醇转化率为100%,乙酸松油酯的选择性为87.2%;并对离子液体(HSO3-pmim)H2PO4的重复使用性能进行了考察,离子液体在不经处理直接重复使用6次后,松油醇的转化率为99.4%,乙酸松油酯的选择性为88.6%,具有较好的重复使用性能。
An acidic functional ionic liquid I-( 3-sulfonic group)propyl-3-methylimidazole dihydrogen phosphate ((HSO3-pmim) H2PO4 ) was synthesized and used to catalyze the esterification of terpineol with acetic anhydride. The influences of reaction condition, such as reaction temperature, reaction time, n(terpineol) :n( acetic anhydride) and amount of acidic functional ionic liquid were examined. The optimum condition for esterification was obtained as follows : n ( terpineol ) : n ( acetic anhydride) 1 :1.5, terpineol 5.1g, ionic liquid 1.5 g, reaction temperature 40℃ and reaction time 8 h. Under the above condition, the conversion of terpineol was 100% and the selectivity of terpinyl acetate was 87.2 %. The recyclability of the ionic liquid was also investigated. When the ionic liquid was repeatedly used for six times, the conversion of terpineol was 99.4%, and the selectivity of terpinyl acetate was 88.6 %. The catalyst for this synthesis has advantages of high yield, simple experimental operation and product isolation, and easy reusability of the catalyst which could be expected to realize an clean and environment- friendly strategy for the production of terpinyl acetate.