Physical Properties of Ionic Liquids Consisting of the 1-Butyl-3-methylimidazolium Cation with Various Anions and the Bis(trifluoromethylsulfonyl)imide Anion with Various Cations

Atom Substitution Effects in Ionic Liquids: A Microscopic View by Femtosecond Raman-Induced Kerr Effect Spectroscopy

“…As listed in Table 1, the surface tension becomes slightly smaller with the heavier element substitution in the aromatic and nonaromatic "cations" but becomes larger with the heavier element substitution in the "anions". There is an inverse correlation between surface tension and molar volume in molten salts, including ILs (Jin et al, 2008). The change in surface tension for the ILs by the heavy atom replacement in the cation is well explained by the empirical scheme.…”

Activity Coefficients at Infinite Dilution for Organic Solutes Dissolved in Three 1-Alkyl-1-methylpyrrolidinium Bis(trifluoromethylsulfonyl)imide Ionic Liquids Bearing Short Linear Alkyl Side Chains of Three to Five Carbons

“…The preparation of the 1-alkyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ILs followed methods reported by Jin et al 9 with particular emphasis focused on precautions essential for accomplishing analytically pure spectroscopic-grade fluids bearing no discernible visual color. 10,11 Succinctly, this requires consideration of five frequently disregarded aspects of the synthesis: (i) single or double distillation of any and all bromoalkane and Nmethylpyrrolidine starting materials; (ii) reaction for the better part of a week at sub-50°C temperatures under flowing inert gas and adequate protection from room light; (iii) several (at least three or four) iterative recrystallizations of the resulting bromide salt; (iv) constant gentle (100−150 rpm) stirring of an aqueous solution of the multiply recrystallized 1-alkyl-1-methylpyrrolidinium bromide with activated carbon (∼1.0 wt % relative to the salt being cleaned; both type DARCO G60 and DARCO KB-G have worked well in our hands) for several days, after which centrifugation (5000 × g for 30 min suffices), cautious decantation, and supernatant syringe filtration (0.45 μm nylon is our filter of choice) are necessary to entirely remove the carbon.…”

Study of Ether-, Alcohol-, or Cyano-Functionalized Ionic Liquids Using Inverse Gas Chromatography

“…The synthesis of 1-ethylmethylether-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C 2 OC 1 mim][Tf 2 N]) and 1-ethanol-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([C 2 OHmim][Tf 2 N]) was performed similarly to that described by Baker and co-workers. [43][44][45] In both cases, the materials obtained were clear, colorless fluids with purities higher than 99.5 % in mass fraction based on thermogravimetric analysis 46 and NMR spectroscopy. NMR spectra of these ILs were measured using a Bruker Avance The solutes were purchased from Aldrich with a purity higher than 99.5 %.…”