Cyclopentadienyl-ruthenium and -osmium complexes VII. Formation and properties of ion-pairs containing the dihydride (η-cyclopentadienyl)bis(triphenylphosphine)-ruthenium(IV) cation

Article abstract of DOI:10.1016/0022-328X(89)85387-2

The ⁺ cation in the simple and fast reaction of CpRuH(PPh3)2 with organic sulphonic acids in polar solvents (methanol, acetone) has been obtained in the form of ion-pairs.The reaction runs for several minutes, with practically quantitative yields.The dihydride complex cation obtained may be isolated from polar solutions as a sparingly soluble ion-pair with the tetraphenylborate anion.In the ion-pairs a reduction-elimination process slowly proceeds with the formation of non-ionic compounds of the CpRu(sulphonate)(PPh3)2 type.Also, the effect of methyl substituents in the Cp-ring on shifts in the 31P NMR signals and MS(FD) investigations of the new compounds obtained have been described.Explanation of the new group signals in the MS(FD) spectra as originating from the fragments formed, containing two ruthenium atoms ?-bonded to the phenyl ring of BPh4, i.e. 6-C6H5)BPh2CpRu(η⁶-C6H5)>⁺, were proposed.In the case of compounds containing the PPh3 molecule, a similar phenomenon occurs.For fragments obtained in the MS(FD) spectra, the formula 6-C6H5)>⁺ was ascribed.