3-Hydroxy-4-methoxybenzaldehyde thiosemicarbazone hemihydrate

Abstract

The asymmetric unit of the title compound, C9H11N3O2S·0.5H2O, comprises two crystallograpically independent thiosemicarbazone molecules (A and B) and a water molecule of crystallization. In each of the thiosemicarbazone molecules, intramolecular O—H...O and N—H...N hydrogen bonds form five-membered rings, producing S(5) ring motifs. Intermolecular O—H...S and N—H...O interactions between molecule B and the water molecule form a six-membered ring, producing an R22(6) ring motif. Intermolecular N—H...S hydrogen bonds form dimers involving pairs of both A and B molecules, which form R22(8) ring motifs. The angles between the aromatic ring and thiourea unit in the two molecules are 0.80 (6) and 3.28 (5)°, which proves that each molecule is fairly planar. The crystal structure is stabilized by intermolecular O—H...S (×2), O—H...O, N—H...S (×2) and N—H...O (×2) hydrogen bonds and C—H...O (×2) contacts to form a three-dimensional network.