α-substitued phosphoryl compounds (IV). The crystal and molecular structure of diethyl[bis-(p-chlorophenoxy)-methan]-phosphonate,C17H19O5PCl2

Diethyl-bis-(p-chlorophenoxy)-methan]-phosphonate crystallizes in the triclinic space group P 1 with two molecules per unit cell. The lattice parameters are a = 8.757 Å, b = 10.479 Å, c = 12.878 Å, α = 82.21°, β = 116.27°, γ = 113.80°. With X-ray diffraction data, collected on an automatic four circle diffractometer, the crystal structure was solved by direct methods and refined to an R-value of 0.049 for 3116 measured and symmetrically independent reflections. The substance is a derivative of acetales of formyl phosphonic acid esters. Correlations between the geometry of the structure and NMR-data are of interest.