Synthesis and characterization of three novel Schiff base compounds: Experimental and theoretical study

Abstract

In this study, three novel Schiff base compounds such as N-(4-nitrobenzyl)-4-methyl bromo aniline (1a), N-(2,4-dimethoxybenzyl)-4-methyl bromoaniline (2a), SN-((1H-indol-3-yl) methylene)-4- methyl bromoaniline (3a) are synthesized and characterized by using the spectroscopic methods of UV, IR and 1H–NMR. Molecular geometry and spectroscopic properties of synthesized compounds are also analyzed by using ab initio calculation methods based on the density functional theory (DFT) in the ground state. The extensive theoretical and experimental FT–IR and UV–vis spectrometry studies of synthesized compounds are performed. The optimized molecular structure and harmonic vibrational frequencies are studied by using B3LYP/6–311++G(d,p) method. Moreover, electronic structures are investigated by using the time dependent density functional theory (TD–DFT) while the energy changes of the parent compounds are examined in a solvent medium by using the polarizable continuum model (PCM). Additionally, the frontier molecular orbital analysis is performed for the Schiff base compounds. The electronic properties of each compound such as; chemical hardness, chemical softness, ionization potential, electron affinity, electronegativity and chemical potential are investigated by utilizing the highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energies. © 2015, Pleiades Publishing, Ltd.