STRUCTURE OF N-(DICHLOROPHOSPHINOYL)PHOSPHORIMIDIC TRICHLORIDE, CL3PNP(O)CL2, AT 100-K

N-(Dichlorophosphinoyl)phosphorimidic trichloride, Cl3PNP(O)Cl2, M(r) = 269.22, monoclinic, P2(1)/c, a 12.573 (5), b = 19.183 (4), c = 14.98 5 (4) angstrom, beta = 110.14 (2)-degrees, V = 3393 (i) angstrom, Z = 16, D(x) = 2.108 Mg m-3, lambda(Mo Kalpha) = 0.71069 angstrom, mu = 2. 02 mm-1, F(000) = 2080, T = 100 K, R = 0.030, wR = 0.032 for 4458 uniq ue observed reflections and 325 parameters. There are four molecules i n the asymmetric unit. The P-N bonds show a pronounced multiple-bond c haracter, the P-N 'double' bonds [1.517 (3)-1.530 (3) angstrom] being substantially shorter than the P-N 'single' bonds [1.583 (3)-1.593 (3) angstrom], and the P-Cl bonds of the P(O)Cl2 groups [1.998 (2)-2.018 (2) angstrom] are clearly longer than the P-Cl bonds of the NPCl3 grou ps [1.956 (2)-1.978 (2) angstrom]. The very flexible P-N-P bond angles lie in the range 137.8 (2)-144.1 (2)-degrees. All four molecules show approximate cisoid conformations with respect to their Cl-P ... P-Cl and Cl-P ... P-O torsion angles. The packing consists of layers normal to the monoclinic axis, each built up of two crystallographically ind ependent molecules with similar environments. In opposition to this, t he molecules in alternating layers show very different arrangements.