CRYSTAL AND MOLECULAR-STRUCTURE OF ORGANOPHOSPHORUS INSECTICIDES .12. DOWCO-214

The crystal and molecular structure of Dowco 214 [O, O-dimethyl O-(3, 5, 6-trichloro-2-pyridyl) phosphorothioate] has been determined by single crystal X-ray techniques. It crystallizes in space group P1 with a = 11.598 (2), b = 13.619 (3), c = 8.281 (1) Å, α = 94.65 (1), β = 94.87 (2), and γ = 79.97 (2)° with four molecules per unit cell (two per asymmetric unit). A modified Patterson superposition procedure yielded an initial model and subsequent least-squares refinement based on 3810 observed reflections (|Fo| > 3σFo) gave a final residual index of R = 0.078. The geometry around the phosphorus is distorted tetrahedral with the P-0 bond to the aryl group being somewhat elongated relative to the others, averaging 1.616 (4) Å vs. 1.560 (4) and 1.547 (4) Å. Charge densities as determined by CNDO methods are also presented, along with appropriate distances between positively charged centers. © 1979, American Chemical Society. All rights reserved.