Structural Studies of an Array of Mixed Diamine Phosphine Ruthenium(II) Complexes1
journal contributionposted on 04.12.2001, 00:00 by Christiane Nachtigal, Samer Al-Gharabli, Klaus Eichele, Ekkehard Lindner, Hermann A. Mayer
Treatment of RuCl2(η2-Ph2PCH2CH2OCH3)2 with various chelating diamines permitted the isolation of the corresponding RuCl2(η1-Ph2PCH2CH2OCH3)2(diamine) complexes in high yield (diamine = 1,2-diaminoethane, 1,2-diaminopropane, 1,3-diaminopropane, 1,2-phenylenediamine, 1,8-diaminonaphthalene, 2,2‘-bipyridine, 1,10-phenanthroline). In solution, all complexes prefer the trans-chloro cis-phosphine arrangement, as deduced by NMR spectroscopy. X-ray studies showed that in the solid state all three possible isomers of the octahedral RuCl2P2(diamine) complexes are present. The reaction of the RuCl2(η1-Ph2PCH2CH2OCH3)2(diamine) complexes with 1 equiv of AgSbF6, AgBF4, or TlPF6 leads to the abstraction of one chloride by simultaneously coordinating one ether oxygen to ruthenium and forming monocationic [RuCl(η1-Ph2PCH2CH2OCH3)(η2-Ph2PCH2CH2OCH3)(diamine)]+ compounds. If a large excess of silver or thallium salt is used, the dichloro complexes are converted to the [Ru(η2-Ph2PCH2CH2OCH3)2(diamine)]2+ dications. In the case of 1,2-phenylendiamine as coligand, the corresponding dication is only observed in traces. NMR spectroscopic investigations and X-ray structural analyses confirm the η1 and η2 coordination of the ether−phosphine ligands in the corresponding mono- and dicationic ruthenium(II) complexes.