Chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium is the organoruthenium half-sandwich compound with formula RuCl(PPh3)2(C5H5). It as an air-stable orange crystalline solid that is used in a variety of organometallic synthetic and catalytic transformations. The compound has idealized Cs symmetry. It is soluble in chloroform, dichloromethane, and acetone.

Preparation

Chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium was first reported in 1969 when it was prepared by reacting dichlorotris(triphenylphosphine)ruthenium(II) with cyclopentadiene.[1]

RuCl2(PPh3)3 + C5H6 → RuCl(PPh3)3(C5H5) + HCl

It is prepared by heating a mixture of ruthenium(III) chloride, triphenylphosphine, and cyclopentadiene in ethanol.[2]

Reactions

Chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium(II) undergoes a variety of reactions often by involving substitution of the chloride. With phenylacetylene it gives the phenyl vinylidene complex:

(C5H5)(PPh3)2RuCl + HC2Ph + NH4[PF6] → [Ru(C:CHPh)(PPh3)2(C5H5)][PF6] + NH4Cl

Displacement of one PPh3 by carbon monoxide affords a chiral compound.[3]

(C5H5)(PPh3)2RuCl + CO → (C5H5)(PPh3)(CO)RuCl + PPh3

The compound can also be converted into the hydride:[4]

(C5H5)(PPh3)2RuCl + NaOMe → (C5H5)(PPh3)2RuH + NaCl + CH2O

A related complex is tris(acetonitrile)cyclopentadienylruthenium hexafluorophosphate, which has three labile MeCN ligands.

Applications

Chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium(II) serves as a catalyst for a variety of specialized reactions. For example, in the presence of NH4PF6 it catalyzes the isomerisation of allylic alcohols to the corresponding saturated carbonyls.[5]

References

  1. ^ Gilbert JD, Wilkinson, G (1969). "New Complexes of Ruthenium(II) with Triphenylphosphine and other Ligands". J. Chem. Soc.: 1749. doi:10.1039/J19690001749.
  2. ^ Bruce, M. I.; Hamiester, C., Swincer, A. G., Wallis, R. C. "Some η5-Cyclopentadienylruthenium(II) Complexes Containing Triphenylphosphine" Inorganic Syntheses 1982, volume 21, pp 78-82. doi:10.1002/9780470132524
  3. ^ Blackmore T, Bruce MI, Stone, F. G. A. (1971). "Some New η-Cyclopentadienyltuthenium Complexes". J. Chem. Soc. A: 2376–2382. doi:10.1039/J19710002376.
  4. ^ Wilczewski, T.; Bochenska, M. & Biernat, J. (1981). "Cyclobentadienyl-Ruthenium Complexes". J. Organomet. Chem. 215: 87–96. doi:10.1016/S0022-328X(00)84619-7.
  5. ^ Murahashi, Shun-Ichi. "Ruthenium in Organic Synthesis" (2006) Wiley-VCH: Weinheim. ISBN 978-3-527-30692-3
Allikas: http://en.wikipedia.org/wiki/Chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium
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