One minute microwave synthesis of [O2N-Ph-CH2-Py = N(Me)2]+[Cl]− ionic liquid: XRD/HSA-interactions, physicochemical, optical, thermal and A DFT/TD-DFT analysis

Abstract

1-(4-nitrobenzyl)-4-dimethylaminopyridinium chloride, [O2N-Ph-CH2-Py = N(Me)2]+[Cl]−, was made available in good yield and within one minute using microwave assisted reaction (MW). The ionic liquid product resonance structure 4-(dimethylamino)-1-(4-nitrobenzyl)pyridin-1-ium (B) was confirmed by XRD-diffraction and solution 15N NMR. Moreover, the FT-IR, UV–Vis., 1H- &13C NMR, were also performed and supported the structure. The packing XRD-data was compared to the molecular electronic potential (MEP) as well as Hirshfeld surface analysis (HSA). The XRD experimental angles/bonds lengths parameters, NMR and IR spectral matched to the theoretical values obtained by DFT/6-311++G(d,p) theory. The optical Tauc experimental energy gap, LUMO/HOMO and Density of State (DOS) energies were also evaluated. The thermal behavior of the ionic liquid under inert and open atmospheres were obtained via TG/DTG in different solvents. The experimental electronic absorption results matched with the Time-dependent (TD-DFT) results.