Research Information System
Journal of Molecular Structure, vol.1304, 2024 (SCI-Expanded)
In this work, azo chromophore group (-N=N-) containing azomethine ligands 2-{(E)-[(2-chlorophenyl)imino]methyl}-6‑methoxy-4-[(E)-phenyldiazenyl]phenol (HL1), 2-{(E)-[(4-chlorophenyl)imino]methyl}-6‑methoxy-4-[(E)-phenyldiazenyl]phenol (HL2) and their Ni(II) and Cu(II) chelates (3–6) were prepared and characterized by the analytical and spectroscopic methods. Single crystals suitable for X-ray diffraction studies were obtained for the prepared azo-azomethine ligands. In the structures of these ligands, there is an intramolecular phenol-imine hydrogen bond (O1-H·····N1) with a distance of 2.580(3)Å. There are also weaker intermolecular hydrogen bond type interactions CH·····O and CH·····N=N stabilising the structures. The ligands behaved as bidentate, coordinating through the nitrogen atom of the azomethine group (CH=N) and the oxygen atom of α‑hydroxyl group (-OH). As a result of analytical and spectral analysis, the metal:ligand ratio was 1:2 in the synthesized copper(II) chelates, while the metal ligand ratio was 1:1 in the nickel(II) chelates. In nickel(II) chelates, one CH3COO− anion and one H2O molecule form a coordination bond with Ni(II) ion. The new bands in infrared spectra of the metal chelates in the region 522–504 cm−1 and 467–455 cm−1 are attributed to ν(M-O) and ν(M-N) vibrations, respectively. The effect of various solvents with different polarities on the UV–visible spectra of the azo-azomethine dyes was studied. Additionally, anti-cancer properties of the synthesized ligands and their metal chelates have also been investigated. The compounds showed relatively higher anticancer properties than 5-FU against HeLa cells.