Synthesis and structural studies of polynuclear ruthenium clusters derived from reactions of 1,2,3,4-tetraphenyl-1,2,3,4-tetraphospholane with [Ru3(CO)12]

Reactions of 1,2,3,4-tetraphenyl-1,2,3,4-tetraphospholane (I) with triruthenium dodecacarbonyl at different temperatures result in the cleavage of P–P bonds and even P–C bond(s) in I to afford a series of new ruthenium cluster derivatives containing phosphido and phosphinidene ligands: a penta-ruthenium wing-tip bridged butterfly cluster [Ru5(CO)11(μ4-PPh)(μ3-PPh){(μ4-η2-(PPh)2CH2}] (1), a hepta-ruthenium polyhedral (consisting of two fused square pyramids with a co-apex) cluster [Ru7(CO)15(μ4-PPh)2{(μ2-PPh)2CH2}](2), a linked penta-ruthenium cluster [Ru4(CO)10(μ4-PPh)(μ3-PPh)2(μ3-η2-PPhCH2)Ru(CO)3] (3), and a hepta-nuclear polyhedral (consisting of two fused square pyramids with different apexes) cluster [Ru7(CO)15(μ4-PPh)2{(μ2-PPh)2CH2}](4). Clusters 2 and 4 are isomeric and differ only in the connection of the two square pyramids in the Ru7 polyhedron. All the newly obtained clusters have been fully characterized by spectroscopic (IR, FABMS, 1H- and 31P-NMR spectroscopy) and analytical techniques, and their molecular structures are established by single crystal X-ray diffraction analysis.