Synthesis, spectral characterization, optical properties and X-ray structural studies of S centrosymmetric N2S2 or N2S2O2 donor Schiff base ligand and its binuclear transition metal complexes

A new chelate namely 2,2'-thiobis(N\-thiophen-2-ylmethyylene) acetohydrazide) (H(2)TTAH) was synthesized and its metal complexes with Co (II), Ni (II), Cu (II), and Zn (II) ions. The isolated complexes were characterized by conventional spectroscopic (IR, UV-visible, ESR, H-1, C-13-NMR, and mass), elemental analysis, and magnetic as well as thermal measurements. H(2)TTAH binds either as neutral tetra dentate and mono-or dibasic NNOOSS hexadentate coordinating two metal ions. The metal complexes afforded the formulae: [Cu-2(TTAH)Cl-3(C2H5OH)(3)]0.5C(2)H(5)OH center dot H2O (1) , [Co-2(TTAH)(C5H5N)]Cl-2 center dot 2.5C(2)H(5)OH (2) , [Ni-2(TTAH)(C5H5N)(2)(OH)(2)(C2H5OH)(2)] (3) and [Zn-2(TTAH)(2))(OH)(4)(C5H5N)(2)]center dot C2H5OH (4) . On the premise of their electronic spectra and magnetic moments data; tetrahedral for Co (II) and octahedral geometries for other complexes were suggested. X-ray powder diffraction technique was used to obtain more details of the chemical constitution of (2) complex. The geometries of all studied compounds were further affirmed by DFT method calculations. Also, all compounds were examined for their antibacterial and superoxide dismutase (SOD)-like activities. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A new chelate H(2)TTAH was synthesized and its metal complexes with Co (II), Ni (II), Cu (II), and Zn (II) ions were characterized. The complexes exhibited different structures and geometries, with tetrahedral for Co (II) and octahedral for other complexes. In addition, the compounds were evaluated for their antibacterial and SOD-like activities.