Catalytic degradation of lignin model compounds in acidic imidazolium based ionic liquids: Hammett acidity and anion effects
Catalytic degradation of lignin model compounds in acidic imidazolium based ionic liquids: Hammett acidity and anion effects
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酸性咪唑基离子液体中木质素模型化合物的催化降解：哈米特酸度和阴离子效应
DOI：
10.1016/j.polymdegradstab.2011.01.011
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发表时间：
2011-04-01
影响因子：
5.9
通讯作者：
Ekerdt, John G.
中科院分区：
文献类型：
--
作者：
Cox, Blair J.;Jia, Songyan;Ekerdt, John G.
以1-甲基咪唑鎓阳离子为基础，配以氯离子、溴离子、硫酸氢根和四氟硼酸根离子，沿着配以1-丁基-3-甲基咪唑鎓硫酸氢根，制备离子液体，用于降解两种木质素模型化合物愈创木基甘油-β-愈创木基醚和藜芦基甘油-β-愈创木基醚。使用3-硝基苯胺作为指示剂来近似每种离子液体的酸度以测量哈米特酸度（H-0）。虽然所有测试的离子液体都是强酸性的（Ho在1.48和2.08之间），但相对酸度与离子液体催化β-O-4醚键水解的能力无关。模型化合物在离子液体中的反应活性不仅取决于离子液体的酸度，还取决于离子的性质及其与模型化合物的相互作用。(C)2011爱思唯尔有限公司保留所有权利。
Ionic liquids based on the 1-methylimidazolium cation with chloride, bromide, hydrogen sulfate, and tetrafluoroborate counterions along with 1-butyl-3-methylimidazolium hydrogen sulfate were employed to degrade two lignin model compounds, guaiacylglycerol-beta-guaiacyl ether and veratrylglycerol-beta-guaiacyl ether. The acidity of each ionic liquid was approximated using 3-nitroaniline as an indicator to measure the Hammett acidity (H-0). While all of the tested ionic liquids were strongly acidic (Ho between 1.48 and 2.08), the relative acidity did not correlate with the ability of the ionic liquid to catalyze beta-O-4 ether bond hydrolysis. The reactivity of the model compounds in the ionic liquids is dependent not only on the acidity, but also on the nature of the ions and their interaction with the model compounds. (C) 2011 Elsevier Ltd. All rights reserved.