Brφnsted Acidic Ionic Liquids as Efficient Reaction Medium for Cyclodehydration of Diethylene Glycol

• 来源期刊: 中国化学（英文版）
• 年，卷（期）: 2008,（8）
• 页码范围: 1390-1394
• 页数: 5页
• 语种: 英文

摘要

Cyclodehydration of diethylene glycol using various Brφnsted acidic ionic liquids as dual solvent-catalysts was studied for the first time. Better results were obtained in the presence of 1-butyl-3-methylimidazolium hydrogen sulfate ([SPmim]HSO4) than other Brφnsted acidic ionic liquids. The effects of reaction conditions such as reaction temperature, reaction time and molar ratio of ionic liquid/diethylene glycol were investigated. Good conversion rate and high selectivity were obtained in ionic liquid [SPmim]HSO4 under the optimum conditions. A Hammett method was used to determine the acidity order of these ionic liquids and the results were consistent with the catalytic ac-tivities observed in the cyclodehydration reaction.