Efficient Synthesis of 1-Acetylpyrene Using [Bmim]Cl–FeCl3 Ionic Liquid as Dual Catalyst and Solvent

Abstract

Abstract Friedel–Crafts acylation of pyrene with acetic anhydride to 1-acetylpyrene catalyzed by three metal chloride and three Lewis acidic ionic liquids (ILs) containing 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) and different metal chloride was investigated. ILs were prepared and tested for the acylation to explore the effects of Lewis acidity of ILs on the synthesis of 1-acetylpyrene. [Bmim]Cl–FeCl3 was found to be the most suitable catalyst, and the possible pathway for the acylation of pyrene with acetic anhydride catalyzed by [Bmim]Cl–FeCl3-IL was discussed. Pure 1-acetylpyrene was obtained and its structure was identified by gas chromatography–mass spectrometer, Fourier transform infrared and 1H NMR spectra.