“…The 2-aryl-1-arylmethyl-1H-1,3-benzimidazoles were obtained in good yields by the reaction of o-phenylenediamine derivatives with various aldehydes in the presence of ferric perchlorate in the absence of solvent at ambient temperature. The method has the ability to tolerate other functional groups such as methyl, methoxy, nitro and chloro groups (Scheme 19) [120].…”