REACTIONS OF CATIONIC (ETA-6-CHLOROARENE) COMPLEXES OF IRON AND RUTHENIUM WITH SOME O-SILYL AND C-SILYL COMPOUNDS

The introduction of an alkylcarbonyl side chain into the aromatic ring of some chloro-substituted benzenes has been achieved under mild conditions by the Yanovsky-type reaction of (eta-6-chloroarene) (eta-5-cyclopentadienyl) cationic complexes of iron or ruthenium with silyl enol ethers. An ester side chain has been introduced similarly using ethyl trimethylsilylacetate. The resulting (eta-5-chlorocyclohexadienyl) (eta-5-cyclopentadienyl) adducts derived from the ruthenium salts are more stable than their iron analogues. Treatment of the neutral ruthenium adducts with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone gives moderate yields of the [eta-6-(substituted chloroarene)(eta-5-Cp)]Ru+ PF6- salt, together with the decomplexed substituted chloroarene.