Synthesis, characterization, thermal studies, and antimicrobial activity of 2-(2-(3,4-dihydronaphthalenylidene)hydrazinyl)-2-oxo-N-phenylacetamide (H₂NHPA) and its transition metal complexes

Abstract

Complexes of Ni(II), Co(II), Cu(II), Cd(II), Hg(II), and U(VI)O₂ with 2-(2-(3,4-dihydronaphthalenylidene)hydrazinyl)-2-oxo-N-phenylacetamide (H₂NHPA) have been prepared and characterized by elemental analysis, molar conductance, thermal (TG, DTG), spectral (¹H NMR, IR, UV–Vis, ESR), and magnetic measurements. IR spectra show that H₂NHPA is a bidentate ligand. Thermal decomposition of some complexes ended with metal oxide as a final product. The room temperature solid state ESR spectra of the Cu(II) complex shows an axial spectrum with ground state, suggesting distorted octahedral geometry around Cu(II). Molecular modeling calculations were used to characterize the complex species. The ligand and its complexes were also evaluated against the growth of some bacteria.

Keywords:

• Hydrazone complexes
• ESR
• Thermal studies
• Molecular modeling
• Biological activities