Design and characterization of nano-silica-bonded 3-n-propyl-1-sulfonic acid imidazolium chloride {nano-SB-[PSIM]Cl} as a novel, heterogeneous and reusable catalyst for the condensation of arylaldehydes with beta-naphthol and alkyl carbamates

摘要

In this research, nano-silica-bonded 3-n-propyl-1-sulfonic acid imidazolium chloride {nano-SB-[PSIM]Cl} as a new and efficient Bronsted acidic ionic liquid supported on silica has been synthesized, and characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, thermogravimetric, differential thermal gravimetric, X-ray diffraction, and energy-dispersive X-ray spectroscopy spectra. The presented silica-supported ionic liquid has been applied as a highly effective, heterogeneous, easy regenerable, and reusable catalytic system for the solvent-free condensation of arylaldehydes with beta-naphthol and alkyl carbamates leading to alpha-carbamatoalkyl-beta-naphthols. Once the nanocatalyst was regenerated and reused, no significant loss of its activity was observed.