Synthesis, characterization and structure of diiron organometallic derivatives of 2,9-dimethyl-1,10-dihydro-dicyclopenta[a,h]naphthalene

The reaction of the dilithium salt of the bridging ligand 2,9-dimethyl-1,10-dihydro-dicyclopenta[a,h]naphthalene with two equivalents of Cp*Fe(acetylacetonate) gives the complex 1 whose structure determination was carried by X-ray crystallography. Oxidation of 1 with ferrocenium affords the corresponding mixed valence compound 2 that exhibits an absorption band at 850 nm. Cyclic voltammetry shows a potential difference of 348 mV between both redox peaks. The Mössbauer investigations at different temperatures show a unique Fe2+ environment for the neutral compound, whereas two sites appear in the mono-oxidized compound which are assigned to Fe2+ and Fe3+.