在离子液体介质中三氯化铟催化缩醛和缩酮反应的研究

Ionic Liquids Immobilized Indium Trichloride Catalyzed Acetalization and Ketalization Reactions

以离子液体为介质研究了三氯化铟催化的缩醛与缩酮反应.在较为适宜的离子液体四氟硼酸1-甲基-3-丁基咪唑盐([BMIm]BF4)中,多种芳香和脂肪族羰基化合物都以适中至高的转化率得到相应的缩醛和缩酮产物.向InCl3/[BMIm]BF4体系中加入溴化1-甲基-3-(2-磺酸钠乙基)咪唑盐后,此复合体系在苯甲醛和甲醇缩合反应中可以至少重复使用5次而保持较高的催化活性.

Acetalization and ketalization reactions catalyzed by indium trichloride using various ionic liquids as media have been investigated in detail.1-n-Butyl-3-methylimidazolium tetrafluoroborate (BF_4) ionic liquid as a catalyst has been proved to be a suitable medium for the title reactions. Many aromatic and aliphatic carbonyl compounds reacted with methanol smoothly in moderate to high conversions. In the presence of an additive (a dialkylimidazolium bromide modified with sodium sulfonate at the end of alkyl group), the catalyst along with the ionic liquid could be reused five times without obviously losing activity in the acetalization of benzaldehyde with methanol.