N-[(E)-Quinolin-2-yl-methyl-idene]-1,2,4-triazol-4-amine hemihydrate

The title hemihydrate, C₁₂H₉N₅·0.5H₂O, was isolated from the condensation reaction of quinoline-2-carbaldehyde with 4-amino-4H-1,2,4-triazole. The Schiff base mol-ecule adopts an E configuration about the C=N bond and is approximately planar, with a dihedral angle between the quinoline ring system and the 1,2,4-triazole ring of 12.2 (1)°. In the crystal, one water mol-ecule bridges two Schiff base mol-ecules via O-H⋯N hydrogen bonds. The Schiff base mol-ecules are inter-connected by π-π stacking inter-actions [centroid-centroid distances of 3.7486 (7) and 3.9003 (7) Å] into columns along [10].