Crystal structure and molecular orbital calculations of trans-1-(2-chloro-4-dimethylaminophenyl)-2-nitroethylene

Abstract

The crystal and molecular structure of the title compound has been determined by three-dimensional X-ray methods and refined to R 0·091 for 1512 independent reflections. The crystals are monoclinic a= 7·44, b= 7·62, c= 19·71 Å, β= 96·0°, space group P2₁/c and Z= 4. The atoms in the molecule are practically coplanar. The bond distances indicate that the π electron systems of the anilino, olefinic, and nitro groups are essentially isolated. These findings are confirmed by molecular orbital calculations on the Pariser–Pople–Parr approach. In the crystal lattice the molecules pack plane-to-plane in pairs about centres of symmetry in stacks in the zone of the b axis. The short interplanar separation is 3·47 Å.