Jump to content

Dichlorotris(triphenylphosphine)ruthenium(II)

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Crackerz21 (talk | contribs) at 04:24, 26 April 2010. The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Dichlorotris(triphenylphosphine)ruthenium(II)
Names
IUPAC name
Dichlorotris(triphenylphosphine)ruthenium(II)
Other names
Ruthenium tris(triphenylphosphine) dichloride; Tris(triphenylphosphine)dichlororuthenium; Tris(triphenylphosphine)ruthenium dichloride;Tris(triphenylphosphine)ruthenium(II) dichloride
Identifiers
ECHA InfoCard 100.035.957 Edit this at Wikidata
EC Number
  • 239-569-7
Properties
C54H54Cl2P3Ru
Molar mass 958.83 g/mol
Appearance Black Crystals or Red-Brown
Density 1.43 g/cm3
Melting point −141 – −139 °C; −222 – −218 °F; 132–134 K
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Dichlorotris(triphenylphosphine)ruthenium(II) is a five coordinate complex of ruthenium. In an inorganic chemistry research lab it is primarily used as a feed stock for more developed and complex ruthenium complexes. In organic chemistry it has found uses in the form of a catalyst.


Synthesis

RuCl2(PPh3)3 is prepared by the reaction of ruthenium trichloride trihydrate with a methanolic solution of triphenylphosphine under inert atmosphere.[1]


2 RuCl3(H2O)3 + 7 PPh3 → 2 RuCl2(PPh3)3 + 2 HCl + 5 H2O + 1 OPPh3


Structure and Basic Properties

The structure of RuCl2(PPh3)3 is five coordinate and octahedral with one of the hydrogen atoms of a phenyl group on the triphenyl phosphine ligands occupying the sixth coordination sites.[2] This Ru---H coordination is long (2.59 Å) and weak. The low symmetry of the compound is reflected with differing bond lengths between Ru-P (2.374 , 2.412 , and 2.230 Å).[3] The Ru-Cl bond lengths are both 2.387 Å.


Substitution Reactions

The triphenyl phospine ligands are labile and are readily substituted by other ligands. Dichlorotris(triphenylphosphine)ruthenium(II) reacts with carbon monoxide to produce all trans-Dichloro(dicarbonyl)bis(triphenylphosphine)ruthenium(II).


RuCl2(PPh3)3 + 2 CO → trans-RuCl2(CO)2(PPh3)2 + PPh3


trans-RuCl2(CO)2(PPh3)2 isomerizes to the cis adduct during recrystallization. Trans-RuCl2(dppe)2 forms upon treating RuCl2(PPh3)3 with dppe.


RuCl2(PPh3)3 + 2 dppe → RuCl2(dppe)2 + 3 PPh3


Organic Reactions

RuCl2(PPh3)3 facilitates oxidations, reductions, cross-couplings, cyclizations, and isomerization. It is used in the Kharasch addition of halogenated species to alkenes.[4]



Dichlorotris(triphenylphosphine)ruthenium(II) serves as a catalyst in the reduction of alkenes, nitro groups, ketones, carboxylic acids, and imines. On the other hand, it catalyzes the oxidation of alkanes to tertiary alcohols, amides to t-butyldioxyamides, and tertiary amines to α-(t-butyldioxyamides) using tert-butyl hydroperoxide. Using other peroxides, oxygen, and acetone, the catalyst can oxidize alcohols to aldehydes or ketones. Using dichlorotris(triphenylphosphine)ruthenium(II) the N-alkylation of amines with alcohols is also possible.[5]



RuCl2(PPh3)3 efficiently catalyzed carbon-carbon bond formation from cross couplings of alcohols through C-H activation of sp3 carbons in the presence of a Lewis acid.[6]



Towards the Development of Hydrogen Fuel Cells

RuCl2(PPh3)3 catalyzes the decomposition of formic acid into carbon dioxide and hydrogen gas in the presence of an amine and dichlorotris(triphenylphosphine)ruthenium(II) with a turnover frequency as high as 2688 h-1 at 40 oC.[7] Since carbon dioxide can be trapped and hydrogenated on an industrial scale, formic acid represents a potential storage and transportation medium.



References

  1. ^ Stephenson, T. A.; Wilkinson, G. “New Complexes of Ruthenium (II) and (III) with Triphenylphosphine, Triphenylarsine, Trichlorostannate, Pyridine, and other Ligands”, J. Inorg. Nucl. Chem., 1966, 28, 945-956. DOI: 10.1016/0022-1902(66)80191-4
  2. ^ Sabo-Etienne, S.; Gellier, M., “Ruthenium: Inorganic and Coordination Chemistry”, Encyclopedia of Inorganic Chemistry, 2006, John Wiley & Sons. DOI: 10.1002/0470862106.ia208
  3. ^ La Placa, S. J.; Ibers, J.A., “A Five-Coordinated d6 Complex: Structure of Dichlorotris(triphenylphosphine)ruthenium(II)”, Inorganic Chemistry, 1965, 4, 778-78. DOI: 10.1021/ic50028a002
  4. ^ Plummer, J. S.; Shun-Ichi, M.; Changjia, Z. “Dichlorotris(triphenylphosphine)ruthenium(II)”, e-EROS Encyclopedia of Reagents for Organic Synthesis, 2010, John Wiley &Sons, Ltd. DOI: 10.1002/047084289X.rd137.pub2
  5. ^ Hamid, M. H. S. A.; Williams, J. M. J., “Ruthenium catalysed N-alkylation of amines with alcohols”, ChemComm. DOI: 10.1039/b616859k
  6. ^ Shu-Yu, Z.; Yong-Qiang, T.; Chun-An, F.; Yi-Jun, J.; Lei, S.; Ke, C.; En, Z.; “Cross-Coupling Reactions between alcohols through sp3 C-H Activation Catalyzed by a Ruthenium/Lewis Acid System” Chem. Eur. J., 2008, 14, 10201-10205. DOI: 10.1002/chem.200801317
  7. ^ Loges, B.; Boddien, A.; Junge, H.; Beller, M., “Controlled Generation of Hydrogen from Formic Acid Amine Adducs at Room Temperature and Application in H2/O2 Fuel Cells”, Angew. Chem. Int. Ed., 2008, 47, 3962-3965. DOI: 10.1002/anie.200705972
Retrieved from "https://en.wikipedia.org/w/index.php?title=Dichlorotris(triphenylphosphine)ruthenium(II)&oldid=358343722"