Green synthesis, characterization and optical properties of eutectics and 1:1 intermolecular compounds: N,N-dimethylaminobenzaldehyde-anthranilic acid and 2-(4-(dimethylamino)benzylideneamino)benzoic acid- p-nitroaniline systems

Abstract

Phase diagrams of N,N-dimethylaminobenzaldehyde (DMAB)-anthranilic acid (AA) and 2-(4- (dimethylamino)benzylideneamino)benzoic acid (DMABAB)-p-nitroaniline (PNA) systems, determined by the thaw-melt method, give two eutectics and a 1:1 intermolecular compound (IMC) in each case. Appropriate amounts (10 g) of each of the eutectics and the IMCs were prepared by a green synthetic method involving a solid state reaction without any solvent. These materials were characterized by X-ray diffraction, thermal and spectral methods and the optical properties of the pure components and the IMCs were studied.While negative values of heat of mixing in the case of a DMAB-AA system suggest clustering of molecules in both eutectic melts, those of positive value in E1 and negative value in E2 of the DMABAB-PNA system indicate the formation of a quasi-eutectic structure in E1 melt and clustering of molecules in E2 melt. The IMC of DMAB-AA system shows strong dual emission with two λmax one at 380 nm and the second at 450 nm with a total quantum efficiency of 0.49. The IMC of DMABAB-PNA system also shows a similar observation with two λmax one at 390 nm and second at 435 nm with a total quantum efficiency of 0.31. © Indian Academy of Sciences.