SYNTHESIS, CHARACTERIZATION AND CRYSTAL-STRUCTURES OF SOME HALF-SANDWICH RUTHENIUM(II) COMPLEXES OF 1,4,7-TRIMETHYL-1,4,7-TRIAZACYCLONONANE CONTAINING PI-ACIDIC ANCILLARY LIGANDS

The synthesis of a series of ruthenium(II) complexes of 1,4,7-trimethyl-1,4,7-triazacyclononane L of type [RuL(X)Y(Z)](+) containing H, O2CCF3, CO, PPh(3), dppe [1,2-bis(diphenylphosphino)ethane] or 2,6-Me(2)C(6)H(3)N=C as auxiliary ligands are described where X = Y = CO, Z = Cl 1; X, Y = dppe, Z = Cl 2; X, Y = dppe, Z = H 3; X = CO, Y = PPh(3), Z = H 4; X = Y = 2.6-Me(2)C(6)H(3)N=C, Z = O2CCF3 5. All complexes were characterized by spectroscopic methods. The crystal structures of 1 and 4 as PF6- salts have been determined. The two CO groups in complex 1 are in cis-fashion with a OC-Ru-CO angle of 90.1(3)degrees and the RU-C distances are 1.850(6) and 1.893(6) Angstrom. Complex 4 features one of the few ruthenium: complexes containing three different piano-stool ligands, namely. CO, PPh(3) and H. The measured RU-CO and Ru-H distances in 4 are 1.785(9) and 1.54(9) Angstrom respectively.