Synthesis, crystal structure and Hirshfeld surface analysis of (3Z)-4-[(4-amino-1,2,5-oxa-diazol-3-yl)amino]-3-bromo-1,1,1-tri-fluoro-but-3-en-2-one.

In the title compound, C6H4BrF3N4O2, the oxa-diazole ring is essentially planar with a maximum deviation of 0.003 (2) Å. In the crystal, mol-ecular pairs are connected by N-H⋯N hydrogen bonds, forming dimers with an R 2 2(8) motif. The dimers are linked into layers parallel to the (10) plane by N-H⋯O hydrogen bonds. In addition, C-O⋯π and C-Br⋯π inter-actions connect the mol-ecules, forming a three-dimensional network. The F atoms of the tri-fluoro-methyl group are disordered over two sites in a 0.515 (6): 0.485 (6) ratio. The inter-molecular inter-actions in the crystal structure were investigated and qu-anti-fied using Hirshfeld surface analysis.

Synthesis, crystal structure and Hirshfeld surface analysis of 3-(4-fluoro-phen-yl)-2-formyl-7-methyl-imidazo[1,2-a]pyridin-1-ium chloride monohydrate.

In the title salt, C15H12FN2O+·Cl-·H2O, the imidazo[1,2-a]pyridin-1-ium ring system of the cation is almostly planar [maximum deviaition = -0.047 (2) Šfor the ring C atom with the attached arene ring] and forms a dihedral angle of 61.81 (6)° with the plane of the fluoro-phenyl ring. In the crystal, water mol-ecules form an R 2 4(8) motif parallel to the (100) plane by bonding with the chloride ions via O-H⋯Cl hydrogen bonds. The cations are connected along the b axis via N-H⋯O hydrogen bonds involving the O atoms of water mol-ecules, and C-H⋯O, C-H⋯Cl and π-π inter-actions [centroid-to-centroid distance = 3.6195 (8) Å] form layers parallel to the (100) plane. Furthermore, these layers are connected via π-π inter-actions [centroid-to-centroid distance = 3.8051 (9) Å] that further consolidate the crystal structure.