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{{chembox
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| verifiedrevid = 428796625
|  Name = Triruthenium dodecacarbonyl
|  ImageFile = Ru3(CO)12.png
|  ImageSize = 200px
|  ImageFile1 = Triruthenium-dodecacarbonyl-from-xtal-3D-balls.png
|  IUPACName = ''cyclo''-tris(tetracarbonylruthenium)<br/>(3 ''Ru''—''Ru'')
|  OtherNames = Ruthenium carbonyl
| Section1 = {{Chembox Identifiers
|  CASNo = 15243-33-1
|    CASNo_Ref = {{cascite}}
  }}
| Section2 = {{Chembox Properties
|  Formula = C<sub>12</sub>O<sub>12</sub>Ru<sub>3</sub>
|  MolarMass =  639.33 g/mol
|  Appearance = orange solid
|  Density = 2.48 g/cm<sup>3</sup>
|  Solubility = insoluble
|  SolubleOther = soluble
|    Solvent = organic solvents
|  MeltingPt = 224 °C
|  BoilingPt = sublimes in vacuum
  }}
| Section3 = {{Chembox Structure
|  CrystalStruct =
|  MolShape = ''D<sub>3h</sub>'' cluster
|  Dipole = 0 [[Debye|D]]
  }}
| Section7 = {{Chembox Hazards
|  ExternalMSDS =
|  MainHazards = Toxic, [[Carbon monoxide|CO]] Source
|  RPhrases =
|  SPhrases =
  }}
| Section8 = {{Chembox Related
|  OtherCpds = [[Triiron dodecacarbonyl]]<br/>[[Triosmium dodecacarbonyl]]
  }}
}}
 
'''Triruthenium dodecacarbonyl''' is the [[chemical compound]] with the formula Ru<sub>3</sub>(CO)<sub>12</sub>. This orange-colored [[cluster chemistry|metal carbonyl cluster]] is a precursor to other [[organoruthenium compound]]s.
 
==Structure and synthesis==
The cluster has ''D<sub>3h</sub>'' [[symmetry group|symmetry]], consisting of an [[equilateral triangle]] of Ru atoms, each of which bears two axial and two equatorial CO ligands.<ref>Slebodnick, C.; Zhao, J.; Angel, R.; Hanson, B. E.; Song, Y.; Liu, Z.; Hemley, R. J., "High Pressure Study of Ru<sub>3</sub>(CO)<sub>12</sub> by X-ray Diffraction, Raman, and Infrared Spectroscopy", Inorg. Chem., 2004, 43, 5245-52. {{doi|10.1021/ic049617y }}</ref>  [[triosmium dodecacarbonyl|Os<sub>3</sub>(CO)<sub>12</sub>]] has the same structure, whereas [[triiron dodecacarbonyl|Fe<sub>3</sub>(CO)<sub>12</sub>]] is different, with two bridging CO ligands, resulting in C<sub>2v</sub> symmetry.
 
Ru<sub>3</sub>(CO)<sub>12</sub> is prepared by treating solutions of [[ruthenium(III) chloride|ruthenium trichloride]] with [[carbon monoxide]], usually under high pressure.<ref>Bruce, M. I.; Jensen, C. M.; Jones, N. L. "Dodecacarbonyltriruthenium, Ru<sub>3</sub>(CO)<sub>12</sub>" Inorganic Syntheses, 1989, volume 26, pages 259-61. ISBN 0-471-50485-8.</ref><ref>M. Faure, C. Saccavini, G. Lavigne "Dodecacarbonyltriruthenium, Ru<sub>3</sub>(CO)<sub>12</sub>" Inorganic Syntheses, 2004 Vol 34, p. 110. ISBN 0-471-64750-0.</ref> The stoichiometry of the reaction is uncertain, one possibility being the following:
:6 RuCl<sub>3</sub>  +  33 CO  +  18 CH<sub>3</sub>OH  →  2 Ru<sub>3</sub>(CO)<sub>12</sub>  +  9 [[dimethylcarbonate|CO(OCH<sub>3</sub>)<sub>2</sub>]]  +  18 HCl
 
==Reactions==
The chemical properties of Ru<sub>3</sub>(CO)<sub>12</sub> 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 to the parent cluster upon standing.
:Ru<sub>3</sub>(CO)<sub>12</sub>  +  3 CO  <math>\overrightarrow{\leftarrow}</math>  3 Ru(CO)<sub>5</sub>  K<sub>eq</sub> = 3.3 x 10<sup>-7</sup> mol dm<sup>–3</sup> at room temperature
The instability of Ru(CO)<sub>5</sub> contrasts with the robustness of the corresponding [[Iron pentacarbonyl|Fe(CO)<sub>5</sub>]]. The [[condensation]] of Ru(CO)<sub>5</sub> into Ru<sub>3</sub>(CO)<sub>12</sub> proceeds via initial, rate-limiting loss of CO to give the unstable, coordinatively unsaturated species Ru(CO)<sub>4</sub>.  This tetracarbonyl binds Ru(CO)<sub>5</sub>, initiating the condensation.<ref>Hastings, W. R.; Roussel, M. R.; Baird, M. C.  "Mechanism of the conversion of [Ru(CO)<sub>5</sub>] into [Ru<sub>3</sub>(CO)<sub>12</sub>]" Journal of the Chemical Society, Dalton Transactions, 1990, pages 203-205. {{doi|10.1039/DT9900000203}}</ref>
 
Upon warming under a pressure of [[hydrogen]], Ru<sub>3</sub>(CO)<sub>12</sub> converts to the [[tetrahedra]]l cluster H<sub>4</sub>Ru<sub>4</sub>(CO)<sub>12</sub>.<ref>Bruce, M. I.; Williams, M. L. "Dodecacarbonyl(tetrahydrido)tetraruthenium, Ru<sub>4</sub>(μ-H)<sub>4</sub>(CO)<sub>12</sub>" Inorganic Syntheses, 1989, volume 26, pages 262-63. ISBN 0-471-50485-8.</ref>  Ru<sub>3</sub>(CO)<sub>12</sub> undergoes substitution reactions with Lewis bases:
:Ru<sub>3</sub>(CO)<sub>12</sub>  +  n L  &rarr;  Ru<sub>3</sub>(CO)<sub>12-n</sub>L<sub>n</sub>  +  n CO (n = 1, 2, or 3)
where L is a tertiary [[phosphines|phosphine]] or an [[isocyanide]].
 
===Ru-carbido clusters===
At high temperatures, Ru<sub>3</sub>(CO)<sub>12</sub> converts to a series of clusters that contain interstitial [[carbide|carbido]] ligands.  These include Ru<sub>6</sub>C(CO)<sub>17</sub> and Ru<sub>5</sub>C(CO)<sub>15</sub>.  Anionic carbido clusters are also known, including [Ru<sub>5</sub>C(CO)<sub>14</sub>]<sup>2-</sup> and the [[octahedral molecular geometry|bioctahedral]] cluster [Ru<sub>10</sub>C<sub>2</sub>(CO)<sub>24</sub>]<sup>2-</sup>.<ref>Nicholls, J. N.; Vargas, M. D. "Carbido-Carbonyl Ruthenium Cluster Complexes"  Inorganic Syntheses, 1989, volume 26, pages 280-85. ISBN 0-471-50485-8ISBN.</ref>
 
Ru<sub>3</sub>(CO)<sub>12</sub> -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==
{{reflist}}
{{Ruthenium compounds}}
 
[[Category:Ruthenium compounds]]
[[Category:Carbonyl complexes]]

Latest revision as of 18:48, 17 July 2014

Greetings! I am Marvella and I feel comfy when individuals use the full name. Hiring has been my profession for some time but I've already applied for an additional one. Doing ceramics is what love doing. Puerto Rico is where he's been living for many years and he will by no means transfer.

Have a look at my web page :: livestudentjobs.co.uk