[en] The complex type [Fe₂(CO)₆(μ-SRS)] are structural analogue of the active site of iron hydrogenases constituted of a dinuclear entity and diatomic ligands CO and CN. The today knowledge on the electrocatalytic activity of some of these organometallic complexes towards the proton reduction in hydrogen^1,2,3, makes possible the elaboration of bio inspired electrocatalysts. Studies must now be realized to better understand the reduction processes of the iron dinuclear complexes with and without acids. In this framework the authors synthesized series of complexes type [Fe₂(CO)_6-n L_n(μ-E-CH₂-X-CH₂-E)] (n=0,1 or 2; L=carbene N-heterocyclic; E=S or P(Ph); X= CH₂, C₆H₄ or NR). (A.L.B.)

[en] The data obtained until now seem to indicate that the hydrogen production by hydrogenases induces a proton-hydride coupling. In taking the structures of theses enzymes active sites (determined by X-ray diffraction) as a basis, it can be thought that this proton-hydride coupling is facilitated by the juxtaposition of two protonation sites, the metallic center M and the basic group of an E ligand of the coordination sphere. Contrarily to the supposed running of the hydrogenases enzymes, the homogeneous catalysts of the protons reduction, described in the literature, present a reactivity which is either on an alone metallic site or on a metal-metal bond. This work deals then with the preparation of complexes having two juxtaposed protonation sites. Some iron dinuclear compounds have been synthesized and their properties studied. (O.M.)