Metal centered oxidation or ligand centered oxidation of metal dithiolene? Spectral, electrochemical and structural studies on a nickel-4-pyridine-1,2-dithiolate system.

摘要: The complex Et4N[Ni(4-pedt)2] (1) (4-pedt = 1-(pyridine-4-yl) ethylene-1,2-dithiolate) was synthesized to investigate the behaviour of metal dithiolene compounds upon protonation and oxidation by absorption spectroscopy, electrochemistry structural analyses further understand electronic states compounds. It is unexpected that 915 nm NIR transition band not shifted when H+ added, it only affected (blue-shifted) compound oxidized. All evidence spectra indicates relevant central [Ni(edt)2] moiety (edt ethylenedithiolate), individual Ni ions or ligands. also intermolecular interaction a dimer. moderately intense appearing at 655 assigned intramolecular charge-transfer between pyridine. redox potentials are sensitive pyridyl group. structures monocationic 1 protonated [Ni(4-Hpedt)2]·ClO4·H2O (2) [Ni(4-Hpedt)2]·PhSO3·2DMF (3) were characterized single crystal X-ray determination. data demonstrate monoanionic neutral does change Ni–S bond distances obviously, which process centered oxidation.