Département de chimie moléculaire

{Abstract Disulfide/thiolate interconversion controlled by Cu is proposed to be involved in relevant biological processes. In analogy to Cu, it can be envisaged that Fe also participates in the control of similar biological processes. We describe here Fe complexes that undergo FeIII-thiolate/FeII-disulfide (inter)conversion mediated by halide (de)coordination, and by the nature of the solvent. The dinuclear FeII-disulfide complex [FeII2(LSSL)]2+ ((LS)2−=2,2′-(2,2′-bipyridine-6,6′-diyl)bis(1,1-diphenylethanethiolate), (LSSL)2−=the corresponding disulfide ligand) shows solvent-dependent properties. Whereas in a non-coordinating solvent (CH2Cl2) the dinuclear FeII-disulfide complex is the only stable form, in the presence of coordinating solvents like MeCN or DMF it is partly or fully converted into mononuclear FeIII-thiolate species having a bound solvent molecule ([FeIII(LS)(Solv)]+