Esterfication reaction of bone acid, pinacol and cyclohexanol has been studied in ionic liquids (IL), including l-methyl-2-pyrrolidonium hydrogen sulfate ([ Hnmp ] HSO4 ) , l-butyl-3-methylimidazolium tetrafluoroborate( [ Bmim ] BF4 ) and l-butyl-3-methylimidazolium hexafluorophosphate ([ Bmim ] PF6 ). The influences of the types of ionic liquids, reaction temperature, reaction time and molar ratio of reactants to IL on the yields of 2-cyclohexyloxy-4,4,5, 5-tetramethyl-[ 1,3,2] dioxaborolan have been investigated. The results showed that under the optimized conditions [ n ( boric acid ) ∶ n ( pinacol ) ∶ n ( cyclohexanol) : n([Hnmp]HSO4) =1∶1∶1∶1, 70 ℃ and 4 h], the yield of 2-cyclohexyloxy-4,4,5,5-tetramethyl-[ 1,3,2] dioxaborolan could reach up to 72.5％. The ionic liquid can be used repeatedly for four times without remarkable loss of the catalytic activity.%研究了硼酸与频哪醇和环己醇在离子液体1-甲基-2-吡咯烷酮硫酸氢盐([Hnmp]HSO4)、1-丁基-3-甲基咪唑四氟硼酸盐([Bmim]BF4)及1-丁基3-甲基咪唑六氟磷酸盐([Bmim]PF6)中生成2-环己氧基-4,4,5,5-四甲基-1,3,2-二氧硼烷的酯化反应.考察了不同离子液体、反应温度、反应时间和离子液体与反应物物质的量比等对反应的影响.结果表明,当n(硼酸):n(频哪醇):n(环己醇):n([Hnmp]HSO4)=1:1:1:1,反应温度为70℃和反应时间为4 h时,硼酸酯的产率为72.5%,离子液体重复使用4次,催化活性无明显降低.
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