Syntheses and Properties of Methoxy and Nitrile Functionalized Imidazolium Tris(pentafluoroethyl)trifluorophosphate Ionic Liquids

Abstract

An alternative and more benign method was employed to synthesize tris(pentafluoroethyl)trifluorophosphate (FAP) ionic liquids (ILs). Ion exchange chromatography was used instead of the typical electrochemical fluorination developed by Ignat’ev and co-workers. The resulting procedure is simple and can be readily performed, as the use of corrosive hydrofluoric acid and the production of toxic and explosive byproducts were circumvented. Functionalization of the alkyl group of the imidazolium cation with a methoxy and a nitrile moiety was employed to observe changes in properties. The success of the synthesis was confirmed by 1H, 19F, and 31P NMR, IR, and UV–vis spectroscopy techniques. Quantitative product yields of approximately 80% (w/w) were obtained. The water content and viscosity values of the synthesized FAP-based ILs were found to be lower compared to other fluorine-containing ionic liquids. Thermal analyses resulted in high thermal degradation temperatures greater than 573.15 K. Electrochemical anal...