Efficient Dehydration of Aldoximes to Nitriles Catalyzed by a Lewis Acid Ionic Liquid
作者:Mizuki Nakajima、Kun Qiao、Nobuhisa Kobayashi、Quanxi Bao、Daisuke Tomida、Chiaki Yokoyama
DOI:10.1246/cl.2011.396
日期:2011.4.5
A Lewis acid ionic liquid, 1-[4-(chlorosulfonyl)butyl]-3-methylimidazolium chlorosulfate ([CBMIm]SO3Cl), with Lewis acid sites in both the anion and cation was synthesized. This was demonstrated to be an efficient catalyst for dehydration of aldoximes to nitriles. An unexpected self-induced phase separation of the reaction mixture was observed when the reaction was carried out in acetonitrile. This could be attributed to the hydrolysis of [CBMIm]SO3Cl to regenerate 1-(4-sulfobutyl)-3-methylimidazolium hydrogensulfate ([SBMIm]HSO4), which was the Brønsted precursor of [CBMIm]SO3Cl.
我们合成了一种路易斯酸离子液体--1-[4-(氯磺酰基)丁基]-3-甲基咪唑氯磺酸盐([CBMIm]SO3Cl),其阴阳离子中均含有路易斯酸位点。实验证明,这是一种高效的催化剂,可将醛肟脱水为腈。在乙腈中进行反应时,观察到反应混合物出现了意想不到的自诱导相分离现象。这可能是由于 [CBMIm]SO3Cl 发生水解,生成了 1-(4-磺丁基)-3-甲基咪唑鎓硫酸氢盐([SBMIm]HSO4),后者是 [CBMIm]SO3Cl 的布氏前体。