Preparation and characterization of polyaniline–1-hydroxyethane 1,1-diphosphonic acid salt and its application as a catalyst for the synthesis of N-benzylidine-2-phenyl imidazo[1,2-a]pyridines


Correspondence to: S. Palaniappan (Email:


A novel, efficient, and easily synthesizable catalyst, an emeraldine form of polyaniline (PANI)−1-hydroxyethane 1,1-diphosphonic acid salt (HEDP), was successfully synthesized and demonstrated as a reusable polymer-based solid acid catalyst in the synthesis of N-benzylidine-2-phenyl imidazo[1,2-a]pyridines with 2-aminopyridine with aromatic aldehydes and trimethyl silylcyanide at room temperature. PANI–HEDP was characterized by Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, field emission scanning electron microscopy, and conductivity measurements. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2995–3000, 2013