A New Three-Component Reaction Catalyzed by Silica Sulfuric Acid: Synthesis of Tetrasubstituted Pyrroles

A novel, convenient, and efficient three-component reaction of benzoin derivatives, 1,3-dicarbonyls, and ammonium acetate in the presence of silica sulfuric acid (SSA) is described for the synthesis of 2,3,4,5-tetrasubstituted pyrroles under solvent-free conditions.