organic compounds
Open access
In the title hydrated salt, C15H11Br2N2+·Cl−·2H2O, the complete imidazolium cation is generated by a crystallographic twofold axis, with one C atom lying on the axis. The chloride ion and both water molecules of crystallization also lie on a crystallographic twofold axis of symmetry. The cation is non-planar, the dihedral angle formed between the central imidazolium and benzene rings being 12.9 (3)°; the dihedral angle between the symmetry-related benzene rings is 25.60 (13)°. In the crystal, O—HCl hydrogen bonds result in supramolecular chains along c mediated by eight-membered {HOHCl}2 synthons. These are consolidated by C—HO and π–π [centroid–centroid distance = 3.687 (3) Å] interactions.
organic compounds
Open access
The title molecule, C12H11N3O4, is essentially planar, the r.m.s. deviation for all non-H atoms being 0.068 Å. An intramolecular C—HN hydrogen bond occurs. The crystal packing is dominated by π–π interactions [shortest centroid–centroid distance = 3.6312 (16) Å], which lead to supramolecular chains that are linked into a three-dimensional network via C—HO contacts. The crystal was found to be a non-merohedral twin (twin law −1 0 0/0 −1 0/ 0.784 0 1), the fractional contribution of the minor component being approximately 22%.