Structural trends in phosphine-substituted [RuCoxRh3–xH(CO)12](x= 0–3) clusters. Crystal structures of [RuCo3H(CO)11(PR3)](PR3= PMe3 or PMe2Ph), [RuCo2RhH(CO)11(PMe2Ph)], [RuCoxRh3–xH(CO)10(PPh3)2](x= 1–2), and [RuRh3H(CO)11(PR3)](PR3= PMe3 or PMe2Ph)

Abstract

The crystal structures of [RuCo₃H(CO)₁₁(PMe₃)], [RuCo₃H(CO)₁₁(PMe₂Ph)], [RuCo₂RhH(CO)₁₁(PMe₂Ph)], [RuCo_1.75Rh_1.25H(CO)₁₀(PPh₃)₂], [RuCoRh₂H(CO)₁₀(PPh₃)₂], [RuRh₃H(CO)₁₁(PMe₃)], and [RuRh₃H(CO)₁₁(PMe₂Ph)] show [Rh₄(CO)₁₂]-like ligand arrangements with phosphines on basal rhodium or cobalt atoms. The phosphines are axially co-ordinated except in the last two compounds, where equatorial co-ordination is found. Hydrides bridge Ru–Rh edges in [RuRh₃H(CO)₁₁(PR₃)](PR₃= PMe₃ or PMe₂Ph) and basal M₃ faces in the other compounds. Geometric parameters are discussed with respect to the metal combination or ligand site.