Synthesis, Characterization and Theoretical Study of New Schiff Bases Derived from 1,8-Diaminonaphthalene and Their Ni(II) Complexes

In this study, we report the synthesis and characterization of some new Schiff base compounds (L1H2, L2H2 and L3H2) derived from the condensation reaction of 1.8-diaminonaphthalene with substituted benzaldehydes (3-NO2, 3,4-OMe and 4-CN) and their nickel (II) complexes. The characterization and nature of bonding have been attained by a means of elemental analysis (C, H and N) and spectral analysis (FT-IR, 1H-NMR and 13C-NMR). The analytical and spectral data are in good agreement with the suggested structures and show a 1:1 molar ratio of the ligand to metal and reveal that the Schiff base ligands are bidentate and coordinate with the Ni (II) ion via the two azomethine nitrogen atoms Theoretical modeling of prepared Schiff base complexes have been conducted using DFT calculations and the obtained results are in good agreement with the experimental data. The computational structural features and relative energies for all the prepared complexes were performed at B3LYP/6-31G(d) and B3LYP/6-31+G(d,p) levels of theory.