Fluoro-functionalized polymeric ionic liquids: highly efficient catalysts for CO₂ cycloaddition to cyclic carbonates under mild conditions

Fluoro-functionalized polymeric ionic liquids (F-PILs) with imidazolium cations and bromide or chloride anions were designed for cycloaddition reactions of CO₂ with epoxides. It was found that the fluorine content in F-PILs significantly influenced the catalytic activity of the catalysts, and F-PIL-Br showed three times higher activity for CO₂ reacting with styrene oxide than non-fluorous PIL-Br. Moreover, F-PIL-Br could be extended to catalyse a broad range of reactants under 1 MPa CO₂ pressure, producing a series of cyclic carbonates in excellent yields (93–99%). In addition, it showed high stability and easy recyclability.