Chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium is the organoruthenium half-sandwich compound with formula RuCl(PPh<sub>3</sub>)<sub>2</sub>(C<sub>5</sub>H<sub>5</sub>). It as an air-stable orange crystalline solid that is used in a variety of organometallic synthetic and catalytic transformations. The compound has idealized C<sub>s</sub> symmetry. It is soluble in chloroform, dichloromethane, and acetone.
Chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium was first reported in 1969 when it was prepared by reacting dichlorotris(triphenylphosphine)ruthenium(II) with cyclopentadiene.
It is prepared by heating a mixture of ruthenium(III) chloride, triphenylphosphine, and cyclopentadiene in ethanol.
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:
Displacement of one PPh<sub>3</sub> by carbon monoxide affords a chiral compound.
The compound can also be converted into the hydride:
A related complex is tris(acetonitrile)cyclopentadienylruthenium hexafluorophosphate, which has three labile MeCN ligands.
Chloro(cyclopentadienyl)bis(triphenylphosphine)ruthenium(II) serves as a catalyst for a variety of specialized reactions. For example, in the presence of NH<sub>4</sub>PF<sub>6</sub> it catalyzes the isomerisation of allylic alcohols to the corresponding saturated carbonyls.