μ-[Bis(η 5-cyclopentadienyl)dimethylsilyl]bis(tricarbonylwolfram), ein über cyclopentadienylliganden verbrücktes bis(η 5-cyclopentadienyltricarbonylwolfram)

Abstract

The reaction of W(CO) 3(EtCN) 3 with (C 5H 5) 2Si(CH 3) 2 leads to the Cp-bridged, binuclear hydrido complex [W(CO) 3H] 2-μ-[(η 5-C 5H 4) 2Si(CH 3) 2] as the main product, whereas only [W(CO) 3] 2-μ-(η 5-C 5H 4) 2Si(CH 3) 2] (I) is formed as the minor product. Much better yields of I can be obtained in the reaction of W(CO) 3(EtCN) 3 with the lithium salt Li 2[(C 5H 4) 2Si(CH 3) 2] and subsequent oxidation. As pointed out by X-ray structure analysis complex I has a cis-configuration with C 2-symmetry due to the linked Cp ligands. In the chiral complex a topomerism can be proved by temperature-dependent NMR spectroscopy.