Spectral, thermal and electrochemical characterization of novel homo-dinuclear complexes [M2(H3DTPA)(H2O)6]Cl2·xH2O (M = Cr2+, Mn2+, Co2+, Ni2+ or Cu2+)

The title complexes were prepared and characterized employing spectral (FAB-Mass, IR, electronic, 1H and 13C NMR), thermal and electrochemical techniques. Analytical and FAB-Mass data suggested a homo-dinuclear stoichiometry. IR and electronic ligand field spectral studies coupled with molecular model computations have indicated a distorted octahedral geometry where the ligand coordinates as a hexadentate dianionic [H3DTPA]2−(H5DTPA = diethylenetriaminepentaacetic acid) moiety. The electrochemical redox properties and the antibacterial activities of the compounds were also investigated.

Graphical abstractThe homo-dinuclear complexes of [H3DTPA]2−(H5DTPA = diethylenetriaminepentaacetic acid) ligand were prepared, characterized employing spectral (FAB-Mass, IR, electronic, 1H and 13C NMR), thermal and electrochemical techniques and tested for antibacterial activities.Figure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► The novel homo-dinuclear complexes of Cr2+, Mn2+, Co2+, Ni2+, and Cu2+ using dianionic ligand [H3DTPA]2− have been synthesized and characterized using various spectral, thermogravimetric and cyclic voltammetric techniques. ► The presence of coordinated and non coordinated (lattice) water molecules were ascertained from thermal studies (TGA). ► The spectral data suggest hexacoordinate distorted octahedral environment around the metal ion. The optimized geometry and the computed structural parameters were obtained employing molecular model computations. ► The cyclic voltammetric studies indicate the presence of quasi reversible CrII/I and CuII/I redox couples in the solutions.