Département de chimie moléculaire

{Disulfide/thiolate interconversion controlled by Cu is proposed to be involved in relevant biol. processes. In analogy to Cu, it can be envisaged that Fe also participates in the control of similar biol. processes. The authors describe here Fe complexes that undergo FeIII-thiolate/FeII-disulfide (inter)conversion mediated by halide 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-=thecorresponding disulfide ligand) shows solvent-dependent properties. The prepd. complexes are [Fe2(LSSL)](ClO4)2 (1), [FeDMF](ClO4) (2) and [CoCp2][FeCl] (3). 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 mol. ([FeIII(LS)(Solv)]+