My watch list
my.chemeurope.com  
Login  

Triruthenium dodecacarbonyl



Triruthenium dodecacarbonyl
General
Systematic name Triruthenium dodecarbonyl
Other names Ruthenium carbonyl
Molecular formula C12O12Ru3
SMILES  ?
Molar mass 639.33 g/mol
Appearance yellow solid
CAS number [15243-33-1]
Properties
Density and phase 2.48 g/cm3
Solubility in water insoluble
Other solvents organic solvents
Melting point 224 °C
Boiling point sublimes in vacuum
Structure
Molecular structure D3h cluster
Crystal structure
Dipole moment 0 D
Hazards
MSDS External MSDS
Main hazards CO source
NFPA 704
R/S statement R: 11-20
S: none
Supplementary data page
Structure and
properties
n, εr, etc.
Thermodynamic
data
Phase behaviour
Solid, liquid, gas
Spectral data IR 2061, 2031, 2011 cm-1
(hexane solution)
Related compounds
Related compounds Fe3(CO)12
Os3(CO)12
Except where noted otherwise, data are given for
materials in their standard state (at 25 °C, 100 kPa)
Infobox disclaimer and references

Triruthenium dodecarbonyl is the chemical compound with the formula Ru3(CO)12. This orange-colored metal carbonyl cluster is an important precursor to organo-ruthenium compounds.

Contents

Structure and synthesis

The cluster has D3h symmetry, consisting of an equilateral triangle of Ru atoms, each of which bears two axial and two equatorial CO ligands.[1] Os3(CO)12 has the same structure, whereas Fe3(CO)12 is different, with two bridging CO ligands, resulting in C2v symmetry.

Ru3(CO)12 is prepared by heating a methanol solution of ruthenium trichloride under a high pressure of carbon monoxide at 250 °C.[2] The stoichiometry of the reaction is uncertain, one possibility being the following:

6 RuCl3 + 33 CO → 2 Ru3(CO)12 + 9 COCl2

Reactions

The chemical properties of Ru3(CO)12 have been well developed and this species can be converted to hundreds of derivatives.

High pressures of CO convert the cluster to the monomeric pentacarbonyl, that reverts back to the parent cluster upon standing.

Ru3(CO)12 + 3 CO → 3 Ru(CO)5 Keq = 3.3 x 10-7 mol dm–3 at room temperature

The instability of Ru(CO)5 contrasts sharply 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.[3]

Upon warming under a pressure of hydrogen, Ru3(CO)12 converts to the tetrahedral cluster H4Ru4(CO)12.[4] Ru3(CO)12 undergoes substitution reactions with Lewis bases:

Ru3(CO)12 + n L → Ru3(CO)12-nLn + n CO

where L is a tertiary phosphine or an isonitrile.

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 Ru5C(CO)142- and the bioctahedral cluster [Ru10C2(CO)24]2-.[5]

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.
  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. ^ Hastings, W. R.; Roussel, M. R.; Baird, M. C. “Mechanism of the conversion of [Ru(CO)5] into [Ru3(CO)12]” Journal of the Chemical Society, Dalton Transactions, 1990, pages 203-205. DOI: 10.1039/DT9900000203
  4. ^ Bruce, M. I.; Williams, M. L. “Dodecacarbonyl(tretrahydrido)tetraruthenium, Ru4(μ-H)4(CO)12” Inorganic Syntheses, 1989, volume 26, pages 262-63. ISBN 0-471-50485-8.
  5. ^ Nicholls, J. N.; Vargas, M. D. “Carbido-Carbonyl Ruthenium Cluster Complexes” Inorganic Syntheses, 1989, volume 26, pages 280-85. ISBN 0-471-50485-8ISBN.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Triruthenium_dodecacarbonyl". A list of authors is available in Wikipedia.
Your browser is not current. Microsoft Internet Explorer 6.0 does not support some functions on Chemie.DE