Mehrfachbindungen zwischen hauptgruppenelementen und übergangsmetallen: XVI. Doppelte oxidative addition von monosilan an das koordinativ ungesättigte organometall-fragment (η5-C5Me5)Mn(CO)2: Darstellung und molekülstruktur von μ-silylen-bis[dicarbonyl(hydrido)(η5-pentamethylcyclopentadienyl)mangan]

Upon treatment of the labile ether complex (η⁵-C₅Me₅)Mn(CO)₂(THF) (1) with monosilane the novel dinuclear complex of composition (μ-SiH₂)(η⁵-C₅Me₅)Mn(CO)₂H]₂ (2) is formed in 15% isolated yield via double oxidative addition of the binary hydride precursor. According to a single-crystal X-ray diffraction study, the molecule exhibits a bent MnSiMn′ framework (≮Mn, Si, Mn′ 124.4(3)°), with the manganese—silicon bond lengths representing single bonds (243.4(3) pm). The resulting distance of 430.6 pm between the manganese atoms precludes any metal—metal bonding so that the complex fragments (η⁵-C₅Me₅)Mn(CO)₂H are exclusively connected to each other via the bridging silylene ligand. The hydrogen ligands attached to the manganese atoms could not be located by X-ray diffraction methods but were detected by NMR spectroscopy (δ(SiH) 4.59, δ(MnH) ?11.55; CDCl₃). Although thermolysis of 2 yields elemental hydrogen, the expected and hitherto unknown complex (μ-Si)(η⁵-C₅Me₅)Mn(CO)₂]₂ is not observed.