The complexes Ru{C(C=CPh)=CPhC(C=CPh)=CPh}(CO)(3)(NMe(3)) (3), Ru-2{mu
-C(C=CPh)=CPhC(C=CPh)=CPh}(CO)(6) (1), Ru-2{mu-[C(C=CPh)=CPh]2CO}(CO)(
6) (2), Ru-3(mu(3)-PhC(2)C=CPh)(mu-CO)(CO)(9) (4) and Ru-4(mu(4)-PhC(2
)C=CPh)(CO)(12) (5) have been isolated from reactions between PhC(2)C(
2)Ph and Ru-3(CO)(12) or Ru-3(CO)(10)(NCMe)(2). The molecular structur
es of complexes 1, 2, 3 and 5 have been determined from single-crystal
X-ray studies. All complexes have precedents in similar products obta
ined from reactions involving mono-ynes; in the present cases, each al
kyne fragment retains a phenylethynyl (PhC=C-) group as a non-coordina
ted substituent.