PREPARATION OF OCTAHEDRAL, HYDRIDO-AQUO-RUTHENIUM(II) COMPLEXES, AND STRUCTURAL CHARACTERISATION OF HYDRIDOAQUODICARBONYLBIS(TRIPHENYLPHOSPHINE)RUTHENIUM(II) TETRAFLUOROBORATE

Article abstract of DOI:10.1016/S0022-328X(00)93469-7

Reaction of RuH2(CO)(PPh3)3 with tetrafluoroboric acid/water gives BF4.Carbonylation of the latter compound yields BF.In the Ir spectra of these compounds, splitting of the asymmetric BF4^- stretching band indicated the possibility of a coordinated tetrafluoroborato ligand, but an X-ray study of BF4 shows that the BF4^- is not coordinated to the metal, but is involved in a network of hydrogen bonds with the coordinated water molecule and the ethanol molecule of crystallisation.The crystal are monoclinic, space group P2₁ with Z = 2 in a unit cell of dimensions a = 9.3959(4), b = 22.695(1), c = 9.7878(3) Angstroem, β - 109.12(1) deg.The observed and calculated densities are 1.39 and 1.404 g cm^-3 respectively.The structure was solved by conventional methods and refined using the full-matrix least-squares equations to final residuals R and R_w of 0.048 and 0.064 respectively.The ruthenium atom is in a distorted octahedral coordination geometry.The Ru-CO distances (1.83 and 1.97(2) Angstroem) differ significantly, with the longer bond situated trans to the hydrido ligand.The Ru-P bonds (2.329 and 2.416(5) Angstroem) are also significantly different, and the P-Ru-P angle is markedly non-linear at 165.1(2) deg.This asymmetry can be attributed to crystal packing forces.