Département de chimie moléculaire

{Disulfide/thiolate interconversion supported by transition-metal ions probably is implicated in fundamental biol. processes, such as the transport of metal ions or the regulation of the prodn. of reactive O species. The authors report herein a mononuclear dithiolate CoIII complex, [CoIIILS(Cl)] (1; LS=sulfur contg. ligand), that undergoes a clean, fast, quant. and reversible CoII disulfide/CoIII thiolate interconversion mediated by a chloride anion. The removal of Cl- from the CoIII complex gives a bis($μ$-thiolato) $μ$-disulfido dicobalt(II) complex, [CoII2,IILSSL]2+ (22+). The structures of both complexes were resolved by single-crystal x-ray diffraction; their magnetic, spectroscopic, and redox properties studied together with DFT calcns. This system is a unique example of metal-based switchable Mn2-RSSR/2 M(n+1)-SR (M = metal ion