Insecticides. Part I. Crystal structures of 1,1-bis-(p-chlorophenyl)-2,2-dichlorocyclopropane and 1,1-bis-(p-ethoxyphenyl)-2,2-dimethylpropane

Abstract

The crystal structure of 1,1-bis-(p-chlorophenyl)-2,2-dichlorocyclopropane, (I), was determined from three-dimensional diffractometer data with 2019 observed reflections by direct methods. Z= 8 in the monoclinic unit cell, space group P2₁/a, with dimensions, a= 1735·1(3), b= 1570·1(3), c= 1111·1(2) pm, and β= 97·09(1)°. The refinement was halted at R 0·061. The x and z projections of the cyclopropane moiety in the molecule are 648 ± 5 pm long, with the projected area at 0·282 ± 5 nm². The height of the y projection is 880 pm. The crystal structure of 1,1-bis-(p-ethoxyphenyl)-2,2-dimethylpropane, (II), was determined from three-dimensional diffractometer data with 947 observed reflections by application of the tangent formula. Z= 4 in the orthorhombic unit cell, space group Pca2₁, with dimensions, a= 2291·2(2), b= 1042·4(1), and c= 786·9(1) pm. The refinement was halted at R 0·035. The main difference with the previous compound is that the ethoxy-groups take up a non-symmetrical trans-configuration. The x and y projection diameters of the neopentane group are 633 pm, projected area 0·288 nm², and height of y, 890 pm.