PUB - Publikationen an der Universität Bielefeld

Metal complexes that are derived from the doubly bridged cyclopentadiene system 2,2,8,8-tetramethyl-2,8-disilatricyclo-[7.3.0.0(3,7)]dodeca-3,5,9,11-tet raene (LH2) are investigated. The dilithio salt of this compound (LLi2) reacts with (Me3Si)3-C5H2FeCl to give, amongst other products, the trinuclear ferrocene [(Me3Si)3C5H2FeL]2Fe (2). A starting material well suited for the selective preparation of similar trinuclear complexes is the mononuclear ferrocene (HL2)Fe (3) which is formed by reaction of HLLi with iron(II) chloride. Reaction of dilithiiated 3 with trimethyltin chloride yields (Me3SnL)2Fe (4). Cocomplexation of dilithiated 3 and Cp*Li(Cp* = C5Me5) with iron(II) chloride leads to the trinuclear ferrocene (Cp*FeL)2Fe (5). By reaction of 3 with octacarbonyldicobalt the heterometallic complex [(CO)2CoL]2Fe (6) is obtained, which yields [(CO)I2CoL]2Fe (7) by oxidative decarbonylation with iodine. The stereochemistry of the complexes presented is discussed. The trinuclear complexes 2, 5, 6, and 7 are model systems for organometallic polymers with spatially directed structures, whose stability even in mixed-valence states is evidenced by the mass spectra of these complexes.