功能化酸性离子液体催化缩醛(酮)的合成

Synthesis of acetals and ketals catalyzed by task-specific acidic ionic liquid

研究了以功能化酸性离子液体1-甲基-3-(4-磺酸基)丁基咪唑硫酸氢盐为催化剂,在无任何有机溶剂的条件下醛(酮)与二元醇的缩合反应,同时考察了催化剂用量、反应时间和反应温度等因素对缩醛(酮)收率的影响。得出最佳反应条件为:反应温度353 K,醛(酮)∶IL(摩尔比)=5∶1,此时缩醛(酮)收率最高可达到93.8%。反应体系无需脱水,产物易于分离,催化剂重复使用5次,其催化活性基本不变。

In the absence of any organic solvents, the acetalization of aldehydes or ketones with diols was investigated, which catalyzed by task-specific acidic ionic liquid under mild conditions. The influences of other conditions including the amount of catalyst, reaction time and temperature on yield of products were also discussed. Results showed the optimal reaction conditions were 353 K, the mole ratio of aldehydes or ketones to IL was 5： 1, the yield of acetals achieved 93.8%. It was unnecessary to remove water produced during the reaction process, the catalyst can be reused for five times without any apparent loss of catalytic activity.