The crystal and molecular structure of hydridotetrakis(diethyl phenylphosphonite)cobalt(I)

D. D. Titus, A. A. Orio, R. E. Marsh, Harry B. Gray
1971 Journal of the Chemical Society D: Chemical Communications  
An X-ray structure determination of the title compound shows that the co-ordination about the cobalt atom is approximately trigonal bipyramidal ; n.m.r. data indicate that the complex is non-rigid in solution. THE syntheses and n.m.r. spectra of HCo[(PhO),P141 and HCo[ (EtO) rP]> have been reported. Although HCo-[(EtO) ,PI4 has been assigned a square-pyramidal configuration on the basis of a temperature-independent highfield quintetJ2 the possibility of a distorted trigonal bipyramidal
more » ... ipyramidal structure with a very low intramolecular rearrangement barrier is attractive.1 We have found the latter possibility in the case of an analogous complex, HCo[(Ph)-P(OEt),]" and report its preparation and structural characterization. A mixture of cobaltous chloride, diethyl phenylphosphonite, and ethanol was treated with a concentrated ethanolic solution of sodium borohydride. After filtration, orange-yellow holohedral prisms separated from the solution (80% yield). In the i.r. spectrum v(C0-H) is observed as a weak band at 2017cm-l (Nujol mull). At room temperature, the high-field n.m.r. spectrum (methylcyclohexane solution) consists of a quintet (T 24.5) with intensity ratios * B. A. Frenz and J.
doi:10.1039/c29710000322 fatcat:kxf5nrynifcb7jwbtkllwxbktm