Bimetallic-induced tail-to-tail dimerization and C-H activation of methyl acrylate

An organometallic complex resulting from tail-to-tail dimerization and C-H activation of methyl acrylate (MA), [Mo(CO)(2)Cp{eta (3)-(MeO2C) CH chemica l anion CH chemical anion CHCH2(CO2Me)] 2, has been fully characterized fro m the reaction of the heterobimetallic complex [Cp*Ni=Mo(mu -CO)(CO)(2)Cp] with MA and an exclusively eta (3)-allyl bonding mode of the coupled ligand was established for the first time by X-ray diffraction; formation of 2 is accompanied by that of the mu (3)-alkylidyne-capped cluster [NiMo2(mu (3)- CCH2CO2Me)(CO)(4)Cp*Cp-2] 3 which results from a double C-H activation of t he CH2 group of MA; none of these reactions occur with the corresponding ho modinuclear complexes.