3-Bromo-6-nitro-1-(prop-2-en-1-yl)-1H-indazole

Abstract

The asymmetric unit of the title compound, C 10 H 8 BrN 3 O 2 , contains two independent molecules differing primarily in the orientations of the allyl substituents [N-C-C C torsion angles = À125.4 (16) and 116.0 (16) ]. The crystal packing involves slipped -stacking of indazole units, together with weak C-HÁ Á ÁO and C-HÁ Á ÁBr hydrogen bonds. The crystal studied was refined as a two-component twin. Structure descriptionStudies of the structure and physicochemical properties of the indazole ring have been reviewed (Abbassi et al., 2014;Li et al., 2003). As a continuation of our studies of indazole derivatives (Mohamed Abdelahi et al., 2017), we now report the synthesis and structure of the title compound (Fig. 1).The asymmetric unit consists of two independent molecules differing primarily in the orientations of the allyl group. Thus, the torsion angles N2-N1-C8-C9 and N5-N4-C18-C19 are, respectively, À77.9 (15) and À71.9 (15) while the N1-C8-C9-C10 and N4-C18-C19-C20 torsion angles are, respectively, À125.4 (16) and 116.0 (16) .In the crystal, offset -stacking interactions between the N1/N2/C1/C2/C7 ring and the N4/N5/C11/C12/C17 ring at Àx + 3 2 , y À 1 2 , Àz + 1 2 form dimers with a dihedral angle between the ring planes of 3.9 (8) and a centroid-centroid distance of 3.494 (8) Å . These dimers are arranged into two sets of oblique stacks, generally along the a-axis direction, by C4-H4Á Á ÁO1 and C18-H1BÁ Á ÁO4 hydrogen bonds (Table 1 and Figs. 2-4). The normals to the stacks are inclined by +/-30.0 (8) to [100] and by 44.7 (8) to each other. Weak C-HÁ Á ÁBr interactions are also observed (Table 1).