Iron hydrogenase active site mimics in supramolecular systems aiming for light-driven hydrogen production

Models of the iron hydrogenase active site [(μ-DT)Fe2(CO)6] (DT: dithiolate) have been synthesized where the dithiolate co-factor bears a functional group to allow for their incorporation into supramolecular systems. Covalently linked to ruthenium(II) polypyridyl photosensitizers, the resulting ruthenium-diiron complexes represent the first members of a new class of dyads designed to promote the light-driven production of hydrogen. The functionalized diiron complexes have been characterized by X-ray crystallography. The redox properties of all complexes were investigated by cyclic voltammetry and the interactions between the photo-excited ruthenium moiety and the diiron unit in these dyads were evaluated by time-resolved spectroscopy.