3-(1H-Imidazol-1-yl)propanaminium picrate

Abstract

In the title salt [systematic name: 3-(1H-imidazol-1-yl)propanaminium 2,4,6-tri­nitro­phenolate], C6H12N3 +·C6H2N3O7 −, there are five independent cation–anion pairs (A, B, C, D, E) in the asymmetric unit. In the cation, the ammonium group is protonated with the amino­propyl group nearly at right angles to the mean plane of the imidazole ring showing C—N—C—C torsion angles ranging from 79.6 (2) to 99.79 (19)° in the five cations. The nitro groups in the anion are twisted from the benzene mean plane with maximum dihedral angles subtended by nitro substituents ortho to the phenolate O atom of 26.0 (2) and 37.3 (7) (A), 28.9 (5) and 35.3 (1) (B), 34.7 (7) and 36.9 (7) (C), 14.7 (4) and 36.9 (2) (D) and 33.1 (1) and 35.4 (3)° (E). In contrast, the nitro groups in the para positions lie much closer to the aromatic ring plane, subtending dihedral angles of 1.8 (3) (A), 3.5 (3) (B), 6.03 (C), 2.1 (3) (D) and 7.7 (1)° (E). Disorder is observed for one O atom of an ortho nitro group in anion D with an occupancy ratio of 0.53 (5):0.47 (5). In the crystal, N—H⋯O cation–anion and N—H⋯N cation–cation hydrogen bonds are observed, linking the ions into chains along [010]. In addition, weak C—H⋯O cation–anion inter­actions occur.