Synthesis, structure, and reactivity of mixed-metal clusters bearing eta(1)-acetylide groups, (eta(5)-C5H5)MFe2(mu(3)-E)(2)(CO)(6)(eta(1)-CCPh) (M = Mo or W and E = Se or Te)

Reaction of Fe-3(CO)(9)(mu(3)-E)(2) (E = Se, Te) with (eta(5)-C5H5)M(CO)(3)(C=CPh) (M = Mo, W); in the presence of trimethylamine-N-oxide (TMNO), in acetonitrile solvent at 60 C yields the novel mixed-metal clusters (eta(5)-C5H5)MFe2(mu(3)=E)(2)(CO)(6)(eta(1)-CCPh) (1, E = Se, M =Mo; 2, E = Se, M = W; 3, E = To, M = Mo; 4, E = Te, M = W) bearing eta(1)-acetylide groups. The reaction of 1 or 3 with dicobalt octacarbonyl at room temperature gives the mixed-metal clusters (eta(5)-C5H5)MoFe2Co2(mu(3)-E)(2)(CO)(9)(mu-CCPh) (5, 6). Structures of 1 and 6 have been established crystallographically