Ionic liquids with fluorine-containing cations

Interest in ionic liquids with fluorine-containing cations has grown markedly in recent years. The syntheses, characterization and properties of quaternary fluoroalkyl- substituted ammonium, imidazolium, triazolium, pyridinium, pyraziniurn, pyridazinium, pyrimidinium, piperazinium, pyrrolidinium., oxazolidinium, and morpholinium. salts have been studied in detail. By modifying the anion or the fluorine-containing substituent on the cation, a wide range of properties of fluorine-containing ionic liquids can be tuned, including viscosity, melting point, density, conductivity, solubility, liquid range, thermal and hydrolytic stability. They are promising solvents for electrochemical, photovoltaic, surfactant and synthetic applications. In this Microreview, only the literature dealing with ionic liquids that involve fluorine-containing cations is presented.