SYNTHESIS AND NMR-SPECTROSCOPY CHARACTERISTICS OF CARBONYLHYDRIDOVANADIUM COMPLEXES STABILIZED BY OLIGOTERTIARY PHOSPHINES

Article abstract of DOI:10.1016/S0022-328X(00)85899-4

Hydridocarbonylvanadium complexes are stabilized by the tri- and tetratertiary phosphines (L) PhP(CH2CH2PPh2)2 (p₃), MeC(CH2PPh2)3 (cp₃), 2 (p₄) and P(CH2CH2PPh2)3 (pp₃).The stable complexes HV(CO)3L and the labile intermediates HV(CO)4L have been prepared by chomatography of the anionic parent compounds on silica gel.Irradiation of HV(CO)3pp₃ and HV(CO)3p₄ affords cis-3> and trans-4>, respectively.The complexes are characterized by their IR, 1H, 31P and 51V NMR spectra.A model of restricted dynamic behaviourbased on the face-capped octahedron is proposed on the basis of the hydride NMR pattern. The dinuclear ligand-bridged 2μ-p₄ is obtained by treatment of 2n<2n(μ-p₄)n> with t-BuCl/H2O.An improved synthesis for the <η⁵-C5H5VH(CO)3>^- anion is described; 1H and 51V NMR data indicate that the local symmetry of the moiety is probably C_3v.