Photochemical irradiation of an equimolar mixture of (eta(5)-C(5)H(5))Fe(CO)(2)SiR(3), FpSiR(3), and FpMe leads to the efficient formation of the silicon-carbon coupled product R(3)SiMe, R(3) = Me(3), Me(2)Ph, MePh(2), Ph(3), ClMe(2), Cl(2)Me, Cl(3), Me(2)Ar (Ar = C(6)H(4)X, X = F, OMe, CF(3), NMe(2). Similar chemistry occurs with related germyl and stannyl complexes at slower rates, Si > Ge> >>Sn. Substitution of an aryl hydrogen in FpSiMe(2)C(6)H(4)R' has little effect upon the rate of the reaction whereas progressive substitution of methyl groups on 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)-C(5)Me(5))Fe(CO)(2) derivatives. A mechanism involving the initial formation of the 16e(-) intermediate (eta(5)-C(5)H(5))Fe(CO)Me followed by oxidative addition of the Fe-Si bond, accounts for the experimental results obtained.
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| http://dx.doi.org/10.1021/om901114q | DOI Listing |
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