Trinuclear benzene clusters of ruthenium and osmium
Abstract
The activated cluster [Os3(CO)7(µ3-η2:η2:η2-C6H6)(C2H4)(MeCN)] reacts with alkynes RC2R′(R = R′= H, Ph or Me; R = H, R′= Ph; R = Me, R′= Et) to produce the new clusters [Os3(CO)7(η6-C6H6)(µ3-η2-RC2R′)] in which the benzene molecule has migrated to a single osmium atom. In contrast, reaction of the ruthenium cluster [Ru3(CO)9(µ3-η2:η2:η2-C6H6)] with similar alkynes RC2R′(R = R′= H, Ph or Me; R = Ph, R′= H) yields the new clusters [Ru3(CO)7(η6-C6H6)(µ3-η2-RC2R′CO)] in which carbonyl insertion has occurred. The molecular structures of [Os3(CO)7(η6-C6H6)(µ3-η2-C2Me2)] and of [Ru3(CO)7(η6-C6H6)(µ3-η2-PhC2PhCO)] have been established by single-crystal X-ray analysis. The C6H6 ligand is η6-bonded to a single metal atom, while the C2Me2 and the PhC2PhCO ligands lie above the metal triangles and are bonded to the three metal atoms via two σ interactions and one π interaction.