Synthesis and Characterization of Linked Clusters Capped by Alkylidyne

The lsolobal displacement reaction between the dianion {M(CO)3[(η5-C5H4) C(O)C6H4C(O)(η5-C5H4)](CO)3M}2－ and two molecules of [(μ3-C)CO2Et]Co3(CO)9 gave rise to the formation of terephthaloyl(biscyclopentadienyl)-bridged double cluster complexes [(η5-C5H4)C(O)C6H4C(O)(η5-C5H4)]{[(μ3-C)CO2Et]Co2M(CO)8}2 (M = Mo 1, M = W, 2). In the reaction, single cluster complexes[(μ3-C)CO2Et]-Co2M(CO)8[η5-C5H4C(O)C6H4CO2CH3] (M = Mo 3, M = W, 4) were yielded as by-products. All the cluster complexes were characterized by C/H analysis, IR and 1H NMR spectroscopy, and the structure of 3 has been determined by single-crystal X-ray diffraction method. Crystal data: Mr = 750.19, monoclinic, space group P21/c, a = 22.652(5), b = 8.954 (2), c = 14.530(3) A, β = 104.00(3)°, V = 2859.6(10) A3, Z = 4, Dc = 1.743 mg/m3, F(000) = 1488, μ = 1.644 mm-1, the final R = 0.0555 and wR = 0.1353 for 5519 observations with I > 2σ(I).