Reactivity of Silylated Dinuclear Iron−Platinum Acyl Complexes: Formation of μ-Vinylidene Complexes and Crystal Structures of the Acyl Complex [(OC)3{(MeO)3Si}Fe(μ-dppm)Pt{C(O)Me}(t-BuNC)] and the μ-Vinylidene Complex [(OC)3Fe{μ-CC(H)Ph}(μ-dppm)Pt(PPh3)]

Addition of RNC to the heterobimetallic acyl complex [(OC)3Fe{μ-Si(OMe)2(OMe)}(μ-dppm)Pt{C(O)Me}] (1a), which displays a μ−η2-Si−O bridge, afforded the isonitrile adducts [(OC)3{(MeO)3Si}Fe(μ-dppm)Pt{C(O)Me}(C⋮NR)] (3a R = t-Bu, 3b R = 2,6-xylyl). Upon treatment of a CH2Cl2 solution of 1a with MeO2CC⋮CCO2Me (DMAD), alkyne insertion into the Pt−C bond gave the alkenyl complex [(OC)3Fe{μ-Si(OMe)2(OMe)}(μ-dppm)Pt{(MeO2C)CC(CO2Me)C(O)Me}] 4. The isonitrile adducts [(OC)3{(MeO)3Si}Fe(μ-dppm)Pt{(MeO2C)CC(O2Me)C(O)Me}(C⋮NR)] (5a R = t-Bu, 5b R = 2,6-xylyl)] were isolated after addition of RNC. A more complex reaction occurred when phenylacetylene or tert-butylacetylene were reacted with 1a. The iron-bound Si(OMe)3 group and the organic ligand coordinated on platinum were eliminated, and the vinylidene-bridged complexes [(OC)3Fe{μ-CC(H)R}(μ-dppm)Pt(CO)] (6a R = Ph, 6b R = t-Bu, 6c R = n-Bu) were obtained. The loosely Pt-bound CO ligand of 6a−c was readily displaced by PPh3, P(OMe)3, or 2,6-xylyl isonitrile yieldi...