Synthesis of 2-Aryl-l-arylmethyl-lH-1,3-benzimidazole Derivatives Using Silica-bonded PropyI-S-sulfonic Acid as Recyclable Solid Acid Catalyst

A highly selective synthesis of 2-aryl-l-arylmethyl-lH-1,3-benzimidazoles from the reaction of o-phenylene- diamine and aromatic aldehydes in the presence of silica-bonded propyl-S-sulfonic acid （SBSSA） at 80℃ in water in good to excellent yields was developed.