Reaction of bis(dimethoxyphosphino)dimethylhydrazine (dmpdmh) with Ru3(CO)12: Evidence for facile ligand fragmentation in Ru3(CO)10(dmpdmh) to give Ru4(CO)12[μ-N(Me)N(Me)], Ru3(CO)11[P(OMe)3], and Ru3(CO)9[μ-P(OMe)3]

Thermolysis of the cluster Ru3(CO)12 with the bis(phosphanyl)hydrazine ligand (MeO)2PN (Me)N(Me)P(OMe)2 (dmpdmh) in toluene at 75°C furnishes the known clusters Ru4(CO)12 [μ-N(Me)N(Me)] (2) and Ru3(CO)11[P(OMe)3] (3), in addition to the new cluster Ru3 (CO)10(dmpdmh) (1) and the phosphite-tethered cluster Ru3(CO)9[μ-P(OMe)3] (4). The simple substitution product Ru3(CO)10(dmpdmh), a logical intermediate to clusters 2–4, was synthesized by treating Ru3(CO)12 with Me3NO in CH2Cl2 at room temperature, and independent thermolysis reactions using cluster 1 was shown to yield clusters 2–4. The solid-state structure of clusters 2 and 4 were unequivocally established by X-ray diffraction analysis. Ru4(CO)12[μ-N(Me)N(Me)] crystallizes in the orthorhombic space group Pnna (#52), a = 12.913(1), b = 13.3238(6), c = 12.5690(8) Å, V = 2162.5(2) Å3, Z = 4, and dcalc = 2.452 g/cm3. Ru3(CO)9[μ-P(OMe)3] crystallizes in the triclinic space group P\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document} $$\bar 1$$ \end{document}a = 9.586(1), b = 14.354(1), c = 14.997(2) Å, α = 89.82(1)°, β = 98.36(1)°, γ = 92.010(8)°, V = 2040.4(4) Å3, Z = 4, and dcalc = 2.212 g/cm3. The coordination of the dimethylazo linkage to the four ruthenium atoms in 2 and the phosphorus atom and one of the oxygen atoms of the methoxy groups to the three ruthenium centers in 4 are confirmed by X-ray analysis.