2,3-Dimethyl-6-nitro-quinoxaline

Abstract

The asymmetric unit of the title quinoxaline compound, C(10)H(9)N(3)O(2), contains two crystallographically independent mol-ecules (A and B). The quinoxaline ring systems are essentially planar, with maximum deviations of 0.006 (1) and 0.017 (1) Å, respectively, for mol-ecules A and B. In mol-ecule A, the dihedral angle formed between the quinoxaline ring system and nitro group is 10.94 (3)° [6.31 (13)° for mol-ecule B]. In the crystal, mol-ecules are linked into chains propagating along [001]: one forms zigzag chains linked by C-H⋯O hydrogen bonds, whilst the other forms ladder-like chains by way of C-H⋯N and C-H⋯O hydrogen bonds. The packing is further consolidated by weak π-π inter-actions [range of centroid-centroid distances = 3.5895 (7)-3.6324 (7) Å].

Fig. 1.

The molecular structure of (I) showing 30 % probability displacement ellipsoids for non-H atoms.

Fig. 2.

Fit of molecule A (dashed lines) on molecule B (solid lines). H atoms have been omitted for clarity.

Fig. 3.

The crystal structure of (I), viewed along the a axis, showing the molecules being linked into one-dimensional chains along the [001] direction. Intermolecular hydrogen bonds are shown as dashed lines.