Preparation of silanediyl-bridged Fe-Fe and Fe-W dinuclear complexes. X-ray structures of [Cp*Fe(CO)(mu-CO){mu-Si(H)CHPh2}(Co)(n)MCp] (CP* = C5Me5, Cp = C5H5, M = Fe, n = 1; M = W, n = 2)

Photolysis of a 2 : 1 mixture of [Cp*Fe(CO)(2)Me] and Ph2CHSiH3 produces ma inly the mononuclear silyl complex [Cp*Fe(CO)(2){Si(H)(2)CHPh2}] (1) togeth er with two silanediyl-bridged diiron complexes: cis- and trans-[Cp*(2) (CO )(2)Fe-2(mu-CO){mu-Si(H)CHPh2}] (2), and [{Cp*Fe(CO)(2)}(2)]. The trans-2 c omplex isomerizes to cis-2 photochemically, but no cis-trans isomerization occurs thermally below 100 degrees C. Photolysis of [CpFe(CO)(2)SiMe3] or [ CpW(CO)(3)Me] in the presence of 1 produces novel silanediyl-bridged comple xes [Cp*Fe(CO)(mu-CO){mu-Si(H)CHPh2}(CO)(n)MCp] (3: M = Fe, n = 1; 4: M = W , n = 2) in moderate yields. Complexes 3 and 4 have been characterized by X -ray diffraction analysis. To the best of our knowledge, complex 4 is the f irst example of a silanediyl-bridged Fe-W complex. The Cp and Cp* rings are mutually cis with the dihedral angle of 78.7(2)degrees in complex 3, but t hey are trans with the dihedral angle of 13.1(6)degrees in complex 4.