Carbon-carbon coupling reactions on triruthenium clusters:: synthesis and structure of Ru3(CO)9[μ3-η3-PhCCCC(H)Ph][μ2-NS(O)MePh] and Ru3(μ2-CO)(CO)7[μ3-η3-PhCCCC(H)Ph][μ3-NS(O)MePh]

The reaction of the electron-deficient cluster (mu(2)-H)Ru-3(CO)(9)[mu(3)-NS(O)MePh] (1) with para-nitrotolane gives, with coupling of two alkyne units and elimination of the para-nitrophenyl fragment, the trinuclear complexes Ru-3(CO)(9)[mu(3)-eta(3)-PhCCCC(H)Ph][mu(2)-NS(O)MePh] (2) and Ru-3(mu(2)-CO)(CO)(7)[mu(3)-eta(3)-PhCCCC(H)Ph][mu(3)-NS(O)MePh] (3). The resulting organic moiety, coordinated as mu(3)-eta(3)-5e-donor, is best considered as a butenynyl (PhC=C-C=C(H)Ph) ligand in 2 and as a butatrienyl (PhC=C=C=C(H)Ph) ligand in 3. From the reaction mixture, the two isomeric vinyl complexes Ru-3(mu(2)-CO)(2)(CO)(6)[mu(2)-eta(2)-PhC=C(H)(C6H4-p-NO2)][mu(3)-NS(O)MePh] (4a) and Ru-3(mu(2)-CO)(2)(CO)(6)[mu(2)-eta(2)-(C6H4-P-NO2)-C=C(H)Ph]-[mu(3)-NS(O)MePh] (4b) complexes can also be isolated. (C) 1997 Elsevier Science S.A.