羧基功能化离子液体催化α-蒎烯水合/异构反应性能

摘要

设计合成了一系列烷基咪唑羧基功能化离子液体,采用FT-IR,1H NMR表征了其结构,采用正丁胺/乙腈电位滴定法分析其酸强度.该类羧基功能化离子液体在α-蒎烯的水油两相酸催化反应中表现出了较高的催化活性,考查了羧基个数、引入卤素等因素对催化性能的影响.结果表明,羧基及卤素基团的引入提高了水合产物的选择性.在催化剂[N-C14,N'-(CO2 H)2-C2 H2-Im-Br]2 HPW12O40用量0.25 mmol,水用量0.30 mol,α-蒎烯用量0.06 mol,80℃反应8h的条件下,α-蒎烯转化率达98.2％,α-松油醇的选择性为21.6％,水合产物的总选择性达33.9％.%A series of CFILs (carboxyl functionalized ionic liquids) had been synthesized via a conventional method.The CFILs catalysts has been applied to the hydration/isomerization of α-pinene and exhibited good catalytic activity.The CFIL of [N-C14,N'-(CO2 H)2-G2 H2-Im-Br]2 HPW was characterized by 1HNMR and FT-IR.And the productions of hydration/isomerization were analyzed via GC-MS and GC.The results indicated that introduction of carboxyl groups had enhanced the selectivity for α-terpineol and halogen group had improved the conversion to a certain extent.Furthermore,the catalyst of [N-C14,N'-(CO2 H)2-C2 H2-ImBr]2HPW12O40 performed the best catalytic effect among these CFILs.Under the optimum reaction conditions that the dosage of catalyst is 0.25 mmol,the dosage of water is 0.30 mol,the amount of α-pinene is 0.06 mol,the temperature is 80 ℃ and the reaction time is 8 h,the conversion of α-pinene was 98.2％,and the selectivity for α-terpineol was 21.6％.