An efficient solvent-free approach for the synthesis of 2-amino benzo[h]chromene derivatives from the condensation of malononitrile, 2-naphthol and various aldehydes using acetic acid functionalized imidazolium salt (1-carboxymethyl-3-methylimidazolium bromide {[cmmim]Br} as a reusable catalysts is reported. In addition, thermal gravimetric analysis (TGA), differential thermal gravimetry (DTG), powder X-ray diffraction (PXRD) and calculation of size and inter planer distance of the catalyst have been studied in this work.
