PTA (H3PO4·12WO3·xH2O): An eco-friendly catalyst for the synthesis of new Schiff-bases containing benzimidazole moiety

In this study H3PO4·12WO3·xH2O is found to catalyze the preparation of Schiff bases from the reaction of 3-(1H-Benzimidazol-2-yl)naphthalene-2-amine with different aldehydes efficiently in ethanol. The advantages of this environmental friendly and mild method are such as simplicity of the reaction procedure, the elimination of solvents, simple work-up, high product yields and short reaction times. The products were characterized by FT-IR 1H NMR, 13C NMR, mass spectrometry and elemental analysis.