Synthesis, spectral characterization (FT-IR and NMR) and DFT (Molecular structure, HOMO-LUMO, NLO) computational studies on some novel (E)-N-phenyl-3,5-dichloropyridin-4-amine and its derivatives

A new series of Schiff bases were synthesized for the first time by the condensation of substituted aldehyde and 3,5-dichloropyridin-4-amine in ethanol (1:1). The structure of Schiff bases were experimentally characterized by using IR and 1H NMR spectroscopic methods. The structural and vibrational properties of the studied molecules were investigated theoretically by performing density functional theory (DFT) to access reliable results to the experimental values and the calculation results showed good agreement with the experimental ones. The calculated HOMO and LUMO energies showed that charge transfer occurs within the molecule. Atomic charges and molecular electrostatic potential (MEP) have been calculated at the B3LYP method and standard 6-31G(d,p) basis set starting from optimized geometry.