BIMETALLIC ALKOXYSILYL COMPLEXES WITH BIS(DIPHENYLPHOSPHINO)METHANE, 2-(DIPHENYLPHOSPHINO)PYRIDINE OR (DIPHENYLPHOSPHINO)ACETOPHENONE LIGANDS - CRYSTAL-STRUCTURE OF [FE(MU-SI(OME)(2)(OME))(CO)(3)(MU-DPPM)PT(C-NR)][PF6] (R=2,6-XYLYL)

The heterobimetallic carbene complexes [Fe(mu-Si(OMe)(2)(OMe)}(CO)(3)(mu-dppm)Pt{=C(CH2)(2)CH(R)O}][PF6] (R = H (2a), Me (2b)) and isonitrile complexes [Fe{mu-Si(OMe)(2)(OMe)}(CO)(3)(mu-dmmp)Pt(C=N-R)][PF6] (R = 2,6-xylyl (3a), or t-butyl (3b)) have been prepared by the reaction of [Fe{mu-Si(OMe)(2)(OMe)}2(CO)(3)(mu-dppm)PtC1] with 3-butyn-1-ol or (+/-)-4-pentyn-2-ol or R-N=C respectively, in the presence of TIPF6. The (trimethoxy)silyl ligand bridges the two metals, as a result of a Si-O --> Pt interaction. The structure of 3a was refined to R = 0.029 and R(n) = 0.041 on the basis of 5764 reflections having F-0(2)>3 sigma(F-0(2)). Upon reaction of cis-[MCl{(PhO)(2)P(OC6H4)}{P(OPh)(3)}] (M = Pt (5a), or Pd (5b)) with K[Fe{Si(OMe)(3)}(CO)(3)(eta(1)-dppm)] (K1a) the ortho-metallated heterobimetallic complexes cis-[Fe{Si(OMe)(3)}(CO)(3)(mu-dppm)Pt{P(OPh)(2)(OC6H4)}] (6a) and trans-[Fe{Si(OMe)(3)}(CO)(3)(mu-dppm)Pd{P(OPh)(2)(OC6H4)}] (6b) were formed. The phosphinopyridine- and ketophosphine-bridged complexes [Fe{Si(OMe)(3)}(Co)(3)(mu-Ph(2)Ppy)Pd(8-mq)] (8) and [Fe{Si(OMe)(3))}(CO)(3){(mu-Ph(2)PCH(2)C(O)Ph}Pd(8-mq)] (10) are described. We also discuss the preparation, dynamic behaviour and spectroscopic properties of heterobimetallic allyl-type complexes ([Fe{Si(OMe)(3)}(CO)(3)(mu-dppm)Ni(eta(3)-C3H5)] (11), [Fe{Si(OSiMe(3))(3)}(CO)(3)(mu-dppm)Pd(eta(3)-C3H5)] (12a), [Fe{SiMe(OSiMe(3))(2)}(mu-dppm)Pd(eta(3)-C3H5)] (12b), [Fe{Si(OMe)(3))(CO)(3)(mu-Ph(2)Ppy)Pd(eta(3)-RC(3)H(4))](R = H (13a) or Me (13b)) and [Fe{Si(OMe)(3)}(CO)(3)(mu-dppm)Pt(eta(3)-C8H13)] (14)). Treatment of [NiCp(PPh(3))Br] with [NEt(3)H]1a yielded the heterobimetallic complex [Fe{Si(OMe)(3)}(CO)(3)(mu-dppm)NiCp] (15).