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Triruthenium dodecacarbonyl

Names
IUPAC names cyclo-tris(tetracarbonylruthenium) (3 Ru—Ru)
Other names Ruthenium carbonyl
Identifiers
CAS Number	15243-33-1
ECHA InfoCard	100.035.701
CompTox Dashboard (EPA)	DTXSID901015348
Properties
Chemical formula	C12O12Ru3
Molar mass	639.33 g/mol
Appearance	orange solid
Density	2.48 g/cm
Melting point	224 °C
Boiling point	sublimes in vacuum
Solubility in water	insoluble
Solubility in organic solvents	soluble
Structure
Molecular shape	D3h cluster
Dipole moment	0 D
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Toxic
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C , 100 kPa). Y verify (what is  ?) Infobox references

Triruthenium dodecacarbonyl is the chemical compound with the formula Ru₃(CO)₁₂. This orange-colored metal carbonyl cluster is a precursor to other organoruthenium compounds.

Structure and synthesis

The cluster has D_3h symmetry, consisting of an equilateral triangle of Ru atoms, each of which bears two axial and two equatorial CO ligands. Os₃(CO)₁₂ has the same structure, whereas Fe₃(CO)₁₂ is different, with two bridging CO ligands, resulting in C_2v symmetry.

Ru₃(CO)₁₂ is prepared by treating solutions of ruthenium trichloride with carbon monoxide, usually under high pressure. The stoichiometry of the reaction is uncertain, one possibility being the following:

6 RuCl₃ + 33 CO + 18 CH₃OH → 2 Ru₃(CO)₁₂ + 9 CO(OCH₃)₂ + 18 HCl

Reactions

The chemical properties of Ru₃(CO)₁₂ have been widely studied, and the cluster has been converted to hundreds of derivatives. High pressures of CO convert the cluster to the monomeric pentacarbonyl, which reverts back to the parent cluster upon standing.

Ru₃(CO)₁₂ + 3 CO ${\displaystyle {\overrightarrow {\leftarrow }}}$ 3 Ru(CO)₅ K_eq = 3.3 x 10 mol dm at room temperature

The instability of Ru(CO)₅ contrasts with the robustness of the corresponding Fe(CO)₅. The condensation of Ru(CO)₅ into Ru₃(CO)₁₂ proceeds via initial, rate-limiting loss of CO to give the unstable, coordinatively unsaturated species Ru(CO)₄. This tetracarbonyl binds Ru(CO)₅, initiating the condensation.

Upon warming under a pressure of hydrogen, Ru₃(CO)₁₂ converts to the tetrahedral cluster H₄Ru₄(CO)₁₂. Ru₃(CO)₁₂ undergoes substitution reactions with Lewis bases:

Ru₃(CO)₁₂ + n L → Ru₃(CO)_12-nL_n + n CO (n = 1, 2, or 3)

where L is a tertiary phosphine or an isocyanide.

Ru-carbido clusters

At high temperatures, Ru₃(CO)₁₂ converts to a series of clusters that contain interstitial carbido ligands. These include Ru₆C(CO)₁₇ and Ru₅C(CO)₁₅. Anionic carbido clusters are also known, including and the bioctahedral cluster .

Ru₃(CO)₁₂ -derived carbido compounds have been used to synthesize nanoparticles for catalysis. These particles consist of 6-7 atoms and thus are all surface, resulting in extraordinary activity.

References

1. Slebodnick, C.; Zhao, J.; Angel, R.; Hanson, B. E.; Song, Y.; Liu, Z.; Hemley, R. J., "High Pressure Study of Ru₃(CO)₁₂ by X-ray Diffraction, Raman, and Infrared Spectroscopy", Inorg. Chem., 2004, 43, 5245-52. doi:10.1021/ic049617y
2. Bruce, M. I.; Jensen, C. M.; Jones, N. L. “Dodecacarbonyltriruthenium, Ru₃(CO)₁₂” Inorganic Syntheses, 1989, volume 26, pages 259-61. ISBN 0-471-50485-8.
3. M. Faure, C. Saccavini, G. Lavigne “Dodecacarbonyltriruthenium, Ru₃(CO)₁₂” Inorganic Syntheses, 2004 Vol 34, p. 110. ISBN 0-471-64750-0.
4. Hastings, W. R.; Roussel, M. R.; Baird, M. C. “Mechanism of the conversion of into ” Journal of the Chemical Society, Dalton Transactions, 1990, pages 203-205. DOI: 10.1039/DT9900000203
5. Bruce, M. I.; Williams, M. L. “Dodecacarbonyl(tetrahydrido)tetraruthenium, Ru₄(μ-H)₄(CO)₁₂” Inorganic Syntheses, 1989, volume 26, pages 262-63. ISBN 0-471-50485-8.
6. Nicholls, J. N.; Vargas, M. D. “Carbido-Carbonyl Ruthenium Cluster Complexes” Inorganic Syntheses, 1989, volume 26, pages 280-85. ISBN 0-471-50485-8ISBN.

• Ruthenium compounds
• Carbonyl complexes