Bimetallic Cluster Complexes: The Synthesis, Structures, and Bonding of Ruthenium Carbonyl Cluster Complexes Containing Palladium and Platinum with the Bulky Tri-tert-butyl-phosphine Ligand
datasetposted on 28.04.2004, 00:00 by Richard D. Adams, Burjor Captain, Wei Fu, Michael B. Hall, Josiah Manson, Mark D. Smith, Charles Edwin Webster
The bis-phosphine compounds M(PBut3)2, M = Pd and Pt, readily eliminate one PBut3 ligand and transfer MPBut3 groups to the ruthenium−ruthenium bonds in the compounds Ru3(CO)12, Ru6(CO)17(μ6-C), and Ru6(CO)14(η6-C6H6)(μ6-C) without displacement of any of the ligands on the ruthenium complexes. The new compounds, Ru3(CO)12[Pd(PBut3)]3, 10, and Ru6(CO)17(μ6-C)[Pd(PBut3)]2, 11, Ru6(CO)17(μ6-C)[Pt(PBut3)]n, n = 1 (12), n = 2 (13), and Ru6(CO)14(η6-C6H6)(μ6-C)[Pd(PBut3)]n, n = 1 (15), n = 2 (16), have been prepared and structurally characterized. In most cases the MPBut3 groups bridge a pair of mutually bonded ruthenium atoms, and the associated Ru−Ru bond distance increases in length. Fenske−Hall calculations were performed on 10 and 11 to develop an understanding of the electron deficient metal−metal bonding. 10 undergoes a Jahn−Teller distortion to increase bonding interactions between neighboring Ru(CO)4 and Pd(PBut3) fragments. 11 has seven molecular orbitals important to cluster bonding in accord with cluster electron-counting rules.