2-Methyl-3-nitrobenzonitrile

The asymmetric unit of the title compound, C8H6N2O2, contains two independent molecules, the aromatic rings of which are oriented at a dihedral angle of 1.68 (3)°. Intramolecular C—H⋯O hydrogen bonds result in the formation of two non-planar six-membered rings, which adopt envelope and twisted conformations. In the crystal structure, intermolecular C—H⋯O hydrogen bonds link the molecules. There are π–π contacts between the benzene rings [centroid–centroid distances = 3.752 (3) and 3.874 (3) Å].

The asymmetric unit of the title compound, C 8 H 6 N 2 O 2 , contains two independent molecules, the aromatic rings of which are oriented at a dihedral angle of 1.68 (3) . Intramolecular C-HÁ Á ÁO hydrogen bonds result in the formation of two non-planar six-membered rings, which adopt envelope and twisted conformations. In the crystal structure, intermolecular C-HÁ Á ÁO hydrogen bonds link the molecules. There arecontacts between the benzene rings [centroidcentroid distances = 3.752 (3) and 3.874 (3) Å ].
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HK2576).

Comment
Benzonitrile is an important pharmaceutical intermediate, many of its derivatives have biological activity and be used as a variety of drugs. Benzonitrile was found to be almost inert toward the combined action of nitrogen dioxide and dioxygen at room temperature (Suzuki et al., 1994). We report herein the crystal structure of the title compound.
The asymmetric unit of the title compound, (Fig. 1), contains two crystallographically independent molecules, in which the bond lengths (Allen et al., 1987) and angles are within normal ranges. Rings A (C2-C7) and B (C10-C15) are, of course, planar, and they are oriented at a dihedral angle of 1.68 (3)°. The intramolecular C-H···O hydrogen bonds result in the formation of two nonplanar six-membered rings C (O2/N2/C1-C3/H1A) and D (O4/N4/C9-C11/H9B). Ring C adopts envelope conformation with O2 atom displaced by 0.690 (3) Å from the plane of the other ring atoms, while ring D has twisted conformation.

Experimental
The title compound is synthesized according to the literature method (Xinhua et al., 2003). Crystals suitable for X-ray analysis were obtained by slow evaporation of an ethanol solution.

Refinement
H atoms were positioned geometrically, with C-H = 0.93 and 0.96 Å for aromatic and methyl H and constrained to ride on their parent atoms, with U iso (H) = xU eq (C), where x = 1.2 for aromatic H and x = 1.5 for methyl H atoms. Fig. 1

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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. Symmetry codes: (i) −x+3/2, y−1/2, −z+3/2; (ii) −x+2, −y+1, −z+2; (iii) −x−1/2, y+1/2, −z+1/2.