ChemInform Abstract: Wells—Dawson Heteropolyacid Supported on Silica: A Highly Efficient Catalyst for Synthesis of 2,4,5-Trisubstituted and 1,2,4,5-Tetrasubstituted Imidazoles.

The multicomponent cyclocondensation of benzil with aromatic aldehydes, an amine and ammonium acetate (or ammonium acetate alone) is efficiently catalyzed by SiO₂-supported Wells—Dawson heteropolyacid to give the polysubstituted imidazole derivatives (IV) and (VI) in high yields.