(E)-3-(2-Chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethyl-N,N-diphenylcyclopropanecarboxamide

The title compound, C21H19ClF3NO, was synthesized from 3-[(E)-2-chloro-3,3,3-trifluoroprop-1-enyl]-2,2-dimethylcyclopropanecarboxylic acid and diphenylamine. The propenyl and carboxamide substituents lie on the same side of the cyclopropane ring plane, with the two methyl substituents on either side of the plane. The phenyl rings of the carboxamide are inclined at an angle of 84.6 (3)° to one another. The F atoms are disordered over two positions; the site occupancy factors are ca 0.6 and 0.4.

The title compound, C 21 H 19 ClF 3 NO, was synthesized from 3-[(E)-2-chloro-3,3,3-trifluoroprop-1-enyl]-2,2-dimethylcyclopropanecarboxylic acid and diphenylamine. The propenyl and carboxamide substituents lie on the same side of the cyclopropane ring plane, with the two methyl substituents on either side of the plane. The phenyl rings of the carboxamide are inclined at an angle of 84.6 (3) to one another. The F atoms are disordered over two positions; the site occupancy factors are ca 0.6 and 0.4.

Related literature
For the preparation of the title compound, see: Liu et al. (2006). For the insecticidal properties of related compounds, see: Punja (1981 Comment 3-((E)-2-Chloro-3,3,3-trifluoroprop-1-enyl)-2,2-dimethyl cyclopropanecarboxylic acid is a very important intermediate in the preparation of tefluthrinan a useful insecticide controlling a wide range of soil insect pests in maize, sugar beet, and other crops (Punja, 1981). Diphenylamine is also a structure which has bioactivity. We reasoned that a structure containing both of these bioactive components may show enhanced insecticidal activity and prepared the title compound (I), whose structure is repoerted here Fig. 1.
The the propenyl and carboxamide substituents lie on the same side of the cyclopropane ring plane, with the two methyl substituents on either side of the plane. The benzene rings of the carboxamide are inclined at 95.4 (3)° to one another. The crystal packing of (I) is shown in Fig. 2.

Experimental
The title compound was prepared according to the method of Liu et al. (2006). The product was recrystallized from methanol and ethyl acetate (5:1, v/v) over 3 days at ambient temperature, giving colourless single crystals of (I).

Refinement
H atoms were positioned geometrically with C-H = 0.93-0.98 Å and refined using riding model with U iso (H) = 1.2Ueq(carrier). The fluorine atoms of the trifluoromethyl group were disordered over two conformations. The occupancy factor for the major component refined to 0.56 (3). Fig. 1. The molecular structure of (I), drawn with 30% probability ellipsoids. H atoms are drawn as spheres of arbitrary radius.

Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.
Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > 2sigma(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.   (11) 0.0020 (7) 0.0097 (7