Abstract
The asymmetric unit of the title co-crystal salt, 1H-imidazol-3-ium 2,4,6-tri-nitro-phenolate monohydrate, C4H7N2+·C6H2N3O7-·H2O, contains one imidazolium cation, one picrate anion and one solvent water mol-ecule of crystallization. The phenolic proton has been transferred to an imidazole N atom. In the crystal, the components are linked by N-H⋯O and O-H⋯O hydrogen bonds into a three-dimensional network which is further consolidated by weak C-H⋯O hydrogen bonds. In addition, π-π stacking inter-actions occur between pairs of imidazolium cations and picrate anions. If only the classical N-H⋯O and O-H⋯O hydrogen bonds are considered, the component ions are linked into a three-dimensional threefold inter-penetrating network of the topological type utp [or (10,3)-d]. Hirshfeld surface analysis indicates the crystal structure is mainly stabilized by H⋯·O contacts of the hydrogen bonds.
Highlights
The asymmetric unit of the title co-crystal salt, 1H-imidazol-3-ium 2,4,6trinitrophenolate monohydrate, C4H7N2+C6H2N3O7H2O, contains one imidazolium cation, one picrate anion and one solvent water molecule of crystallization
– stacking interactions occur between pairs of imidazolium cations and picrate anions
If only the classical N—H O and O—H O hydrogen bonds are considered, the component ions are linked into a three-dimensional threefold interpenetrating network of the topological type utp [or (10,3)-d]
Summary
Co-crystallization, which is the crystallization of more than one solid component into a new compound, is widely involved in the research fields of active pharmaceuticals (Aitipamula et al, 2015; Weyna et al, 2012; Robinson, 2010; Arenas-Garcıa et al, 2010) and crystal engineering (Manoj et al, 2014). By controlling one specific crystallization condition such as solvent, temperature, pressure or molar ratio of the raw materials, some polymorphs can be obtained with the same ingredients. Two imidazolium picrate co-crystal salts have been reported that were crystallized from chloroform (Soriano-Garcıa et al, 1990) or dry acetonitrile (MorenoFuquen et al, 2011). In order to further research the factors affecting this crystallization process, the crystallization solvent has been adjusted to be methanol (95%). Some yellow needle-shaped crystals were obtained after two days on the side of the vessel and when the solvent had almost evaporated, several yellow block-shaped crystals formed at the bottom of the vessel (Fig. 1a and 1b). The results of X-ray diffraction indicates that the structure of the block-shaped crystals is the same as that reported by Moreno-Fuquen et al. The crystal structure of the needle-shaped crystals is reported.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Acta crystallographica. Section E, Crystallographic communications
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
