Novel NNO pincer type Schiff base ligand and its complexes of Fe(IIl), Co(II) and Ni(II): Synthesis, spectroscopic characterization, DFT, antibacterial and anticorrosion study

Abstract

A novel NNO pincer type ligand (E)-N'-(phenyl(pyridin-2-yl)methylene)isonicotinohydrazide, PPMINH, was synthesized by condensation of 2-benzoyl pyridine and isonicotinylhydrazide. The ligand PPMINH on reaction with metal ions Fe(III), Co(II) and Ni(II) yielded six metal derivatives. Different analysis tools like; Elemental analyses, ESI-MS, FT-IR, molar conductivity, UV-spectra, magnetic susceptibility, NMR and EPR measurement were used. Theoretical FT-IR, 1H NMR and 13C NMR of ligand and complex 6 exhibits quite a good correlation coefficient. EPR spectrum of complex 6 at LNT suggests octahedral geometry around Ni(II). The ligand and complexes were screened for antibacterial activity. DFT has been carried out to optimize the geometry of the ligand and complexes. The properties most relevant to their potential action as corrosion inhibitors has been calculated all parameters of DFT from the inhibitor molecule to the metal atom. The corrosion inhibition effect of compounds on mild steel in an acidic medium was studied for 24, 48, 72 h using weight loss measurement.