Synthesis, absorption, and adsorption properties, and DFT calculations of two new palladium(II) complexes of new fluorescence imidazo[4′,5′:3,4]benzo[1,2-c]isoxazole-based Schiff-bases

Abstract

Two new Pd(II) complexes were prepared from two novel fluorescent heterocyclic bidentate ligands synthesized by the reaction of 8-(4-chlorophenyl)-3-alkyl-3H-imidazo[4′,5′:3,4]benzo [1,2-c]isoxazol-5-amine with p-methoxybenzaldehyde and p-nitrobenzaldehyde in good yields. Indeed the ligands reacted with Pd(II) ion to yield new complexes. Schiff base ligands and their metal complexes were characterized by elemental analyses, IR, UV–vis, mass, and NMR spectra. The optical properties of the compounds were investigated and the results showed that they exhibited interesting photophysical properties. Optimized geometries and assignment of the IR bands for the new complexes were also computed by using density functional theory (DFT) methods. The DFT-calculated vibrational wavenumbers are in good agreement with the experimental values, confirming suitability of the optimized geometries for Pd(II) complexes.