Formation and chemistry of the homologous series of nitrido clusters: [Ru4N(CO)12]-, [Ru5N(CO)14]-, and [Ru6N(CO)16]-

Article abstract of DOI:10.1021/om00120a009

The reaction of coordinated isocyanate ligands to give new nitrido clusters is explored. The thermolysis of [Ru₄(NCO)(CO)₁₃]^- gives [Ru₄N(CO)₁₂]^- in 78% recrystallized yield after 24 h. When the trinuclear isocyanate clusters [Ru₃(NCO)(CO)₁₀]^- and [Ru₃(NCO)(CO)₁₁]^- are heated with 1 equiv of Ru₃(CO)₁₂, the hexanuclear nitrido cluster [Ru₆N(CO)₁₆]^- can be isolated in 82% yield. [Ru₆N(CO)₁₆]^- reacts rapidly with CO at room temperature to give [Ru₅N(CO)₁₄]^- in quantitative yield. A single-crystal X-ray crystallographic study of (PhCH₂Et₃N)[Ru₅N(CO)₁₄] [P1 space group, a = 12.123 (6) ?, b = 14.263 (5) ?, c = 10.642 (3) ?, a = 104.74 (3)°, β = 93.28 (3)°, γ = 80.25 (4)°, Z = 2] revealed a square-based pyramid of metal atoms with the nitrogen positioned slightly below the square face. Other interconversions among the nitrido clusters are also discussed. At high CO pressure, the isocyanate ligand can be reformed from the nitrido clusters.