2,5-Dimethyl-1,3-dinitrobenzene

Abstract

The title compound, C8H8N2O4, was prepared via the nitration of p-xylene. The molecules are stacked along the c axis in an antiparallel manner. The two nitro groups are rotated relative to the benzene ring with dihedral angles of 44.50 (7) and 31.67 (8)°. The tilt of the nitro groups allows the formation of C—H...O interactions between the ring C—H and nitro groups of adjacent molecules creating puckered sheets perpendicular to the c axis. The H atoms of the methyl group in the 5-position are disordered (60° rotation) with an occupancy of 0.616 (19) for the major component. The crystal was found to be a non-merohedral twin with a twin law [−1 −0.002 0.005, 0.00031 −1 0.002, 0.118 −0.007 1] corresponding to a rotation of 180° about the reciprocal axis (001) and refined to give a minor component fraction of 0.320 (2)

The relation between crystal structure and the occurrence of quantum-rotor induced polarization

“…Compounds 8 and 12 were further investigated, since they were the most promising candidates of this series. Interestingly, their methyl groups are in almost perfect face-to-face alignment (see Figure 5 (Johnston and Crather, 2011) and Figure 6 (Wang and Yan, 2015)). On the other hand, they differ in the alignment of the attached phenyl rings compared to 1.…”

“…For compounds 7 to 11, depending on the solubility between 50 and 100 µmol substance were used and in the case of 12 only 30 µmol was suitable. (AYOYAP) (Johnston and Crather, 2011). The distance between them is 3.55 Å (measured carbon to carbon).…”

“…Figure 5: Example for methyl pairs in the crystal structure of 8 (AYOYAP)(Johnston and Crather, 2011). The distance between them is 3.55 Å (measured carbon to carbon).…”

“…Figure 7: XRD spectra of 8. Top: experimental data , bottom: simulated spectrum from crystal structure data(Johnston and Crather, 2011).…”