Synthesis and Characterization of Imidazolium-Based Ionic Liquids

N-methylimidazole, iron (III) chloride anhydrous, 1-chlorobutane, Ethyl acetate, Dibenzyl disulfide (98%), n-hexadecane (98%), N-methyl-pyrrolidone (NMP), PEG-400, and cyclohexane were purchased from Macklin (Shanghai, China). 1-butyl-3-methylimidazolium dicyanamide [BMIM]N(CN)₂, 1-butyl-3-methylimidazolium thiocyanate [BMIM]SCN, 1-butyl-3-methylimidazolium dibutyl phosphate [BMIM](C₄H₉O)₂PO₂, 1-butyl-3-methylimidazolium methyl sulfate [BMIM]MeSO₄, 1-butyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide [BMIM]NTf₂, 1-butyl-3-methylimidazolium trifluoromethanesulfonate [BMIM]OTf, 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM]PF₆, and 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM]BF₄ were provided by Shanghai Cheng Jie Chemical Co., Ltd. (Shanghai, China). All reagents were of analytical grade.