Hydrogen Bond Basicity of Anions

Recently, the ionic liquids [EMIM]NbF6 and [EMIMJTaF have been reported (46). These melt at temperatures slightly below room temperature and have the 

The cations in ionic liquids are generally bulky monovalent organics. The typical cations of ionic liquids, not including the familiar alkylammonium and alkylphosphonium ions, are shown in Fig. 2. It is primarily the cations, which account for the low melting points of ionic liquids. The dialkylimidazolium ions, such as 1-butyl-3-methyl imidazolium [BMIM], have been widely investigated because low-melting ionic liquids can be made readily from such cations and because of their thermal and chemical stability. 

A number of other substituted imidazolium ions have also been reported. [MIM-C2H50CH3]Br and [MIM-CH30CH3]Br, liquids at room temperature, were recently reported to be good solvents for carbohydrates and proteins (47). The diversity of organic cations was extended even to include the antifungal drug miconazole, which contains an imidazole ring. By the reaction of the miconazole with alkyl iodide, bioactive cations were obtained that were subsequently used to form ionic liquids with PF (9). 

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