One-pot Preparation of ۲,۴,۵-Trisubstituted and ۱,۲,۴,۵-Tetrasubstituted Imidazoles Using Poly(۴-vinylpyridinium Butane Sulfonic Acid) Hydrogen Sulfate, as an Efficient Heterogeneous Poly(ionic Liquid) Solid Acid Catalyst under Solvent-free Conditions

One-pot preparation of ۲,۴,۵-trisubstituted and ۱,۲,۴,۵-tetrasubstituted imidazoles has been conducted in the presence of poly(۴-vinylpyridinium butane sulfonic acid) hydrogen sulfate, P(۴VPBSA)HSO۴, as an efficient dual acidic catalyst under solvent-free conditions. Reusability of the catalyst, easy work-up procedure, eco-friendly reaction conditions, short reaction times and high yields of the products illustrate the utility of this approach.

Keywords:

Solvent-free , Substituted imidazoles , Poly(ionic liquid) , Benzil , Multicomponent reaction