Formation of Silicon-Carbon Bonds by Photochemical Irradiation of (η5-C5H5)Fe(CO)2SiR3 and (η5-C5H5)Fe(CO)2Me to Obtain R3SiMe

Photochemical irradiation of all equimolar mixture of (eta(5)-C5H5)Fe(CO)(2)SiR3, FpSiR(3), and FpMe leads to the efficient formation of the silicon-carbon-coupled product R3SiMe, R-3 = Me-3, Me2Ph, MePh2, Ph-3, CIMe2, Cl2Me, Cl-3, Me2Ar (Ar = C6H4-p-X, X = F, OMe, CF3, NMe2)- Similar chemistry occurs with related germyl and stannyl complexes at slower rates, Si > Ge >= Sn. Substitution of an aryl hydrogen to form FpSiMe(2)C(6)H(4)-p-X has little effect on the rate of the reaction, whereas progressive substitution of methyl groups Oil silicon by Cl slows the process. Also, changing FpMe to FpCH(2)SiMe(3) dramatically slows the reaction as does the use of (eta(5)-C5Me5)Fe(CO)(2) derivatives. A mechanism involving the initial formation of the 16e(-) intermediate (eta(5)-C5H5)Fe(CO)Me followed by oxidative addition of the Fe-Si bond accounts for the experimental results obtained.