【摘要】 考察了卤化1甲基3丁基咪唑氯铝酸盐类室温离子液体对甲苯选择性羰基化反应合成对甲基苯甲醛的催化性能.采用乙腈探针红外光谱法测定了离子液体的酸类型(Br¨onsted/Lewis酸),并指示了离子液体的Lewis酸强度.研究了离子液体的酸强度、反应温度、反应时间和CO压力的影响.结果发现,该类离子液体对甲苯选择性羰基化反应的催化活性明显高于传统的BL复合液体酸类和固体超强酸类催化剂;使用离子液体催化剂显著地提高了甲苯选择性羰基化合成对甲基苯甲醛的产率,简化了产物与催化剂的分离.当控制反应温度为50℃,CO压力为4.0MPa,反应时间为4h时,[bmim]Br/AlCl3催化甲苯的转化率可达96%,目标产物对甲基苯甲醛的产率达86%.更多还原

【Abstract】 Halogenated 1-butyl-3-methylimidazolium chloroaluminate room-temperature ionic liquids were used to catalyze the selective carbonylation of toluene to p-tolualdehyde. Acetonitrile was utilized as an IR molecular probe to determine the acid type （Brnsted or Lewis acid） and Lewis acid strength of the ionic liquids. The effects of reaction conditions such as reaction temperature, reaction time, and CO pressure on the reaction were investigated. When [bmim]Br/AlCl₃ was used as the catalyst, a high toluene conversion of 96% and a high p-tolualdehyde yield of 86% could be obtained at a reaction temperature of 50 ℃, reaction time of 4 h, and CO pressure of 4.0 MPa. The results showed that the ionic liquids exhibited better catalytic performance for the selective carbonylation of toluene to p-tolualdehyde than the B-L compound liquid acids and solid acids.更多还原