Mononuclear Ruthenium and Hetero-Tetranuclear Ruthenium-Silver Complexes Containing the Unsymmetrical Bidentate Ligands R2P(CH2)nER′2 (n = 1, 2; E = P, As) as Chelating or Bridging Units

The chelate complexes [(p-cym)RuCl(κ2-Ph2PCH2CH2AstBu2)]PF6 (3), [(arene)RuCl(κ2-Ph2PCH2CH2PR2)]PF6 (4, 7, 8) and [(p-cym)RuCl(κ2-iPr2PCH2AstBu2)]PF6 (11) were prepared either from [(arene)RuCl(NCMe)2]PF6 (1, 5) or from [(arene)RuCl2]2 (2, 6), in the presence of NH4PF6 or AgPF6. The stepwise reaction of [(p-cym)RuCl2]2 (2) with Ph2PCH2CH2PtBu2 and AgPF6 gave the hetero-tetranuclear compound [{(p-cym)RuAg(μ-Cl)2(μ-P1Ru,P2Ag-Ph2P1CH2CH2P2tBu2)}2](PF6)2 (9), the structure of which was determined by an X-ray crystal structure analysis. The bidentate As,O donor Ph2P(O)CH2CH2AstBu2 also reacted with 2, in the presence of AgPF6, to afford the chelate complex [(p-cym)RuCl{κ2(As,O)-Ph2P(O)CH2CH2AstBu2}]PF6 (10), which was also characterized crystallographically.