2-Allyl-7-nitro-2H-indazole

Abstract

The asymmetric unit of the title compound, C10H9N3O2, contains two independent mol-ecules linked by a C-H⋯N hydrogen bond. Each mol-ecule has a similar conformation, being built up from fused five- and six-membered rings, each linked to an ally and nitro group, respectively. The indazole ring system makes dihedral angles of 2.7 (2) and 2.2 (2)°, respectively, with the plane through the nitro group. The allyl group is nearly perpendicular to the indazole system, as indicated by the N-N-C-C torsion angles of -75.3 (2) and -82.2 (2)°, this being the most important difference between the conformations of the two mol-ecules. In the crystal, mol-ecules are linked by C-H⋯O and π-π [inter-centroid distance = 3.6225 (8) Å] inter-actions to form a three-dimensional network.

Fig. 1.

The two molecules comprising the asymmetric unit of the title compound with the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are represented as small circles.

Fig. 2.

Overlay diagram of the two crystallographically independent molecules highlighting the different orientations of the allyl groups.