7-Chloro-4-[(E)-2-(4-methoxybenzylidene)hydrazin-1-yl]quinoline monohydrate

The organic molecule in the title hydrate, C17H14ClN3O·H2O, has a small but significant twist from planarity, as seen in the dihedral angle of 12.10 (17)° between the quinoline and benzene rings. The conformation about the C=N bond is E. Chains along the b axis are formed in the crystal structure aided by water–quinoline O—H...N (× 2) and hydrazone–water N—H...O hydrogen bonds. Layers of these chains stack along the a axis via C—H...π and π–π interactions [ring centroid–ring centroid distance = 3.674 (2) Å]. C—H...O interactions are also present.