4-[2-(4-Chlorophenyl)hydrazinylidene]-3-methyl-1H-pyrazol-5(4H)-one

Abstract

In the title compound, C10H9ClN4O, the pyrazole ring [maximum deviation = 0.014 (2) Å] forms a dihedral angle of 7.06 (14)° with the chlorobenzene ring. The molecular conformation is stabilized by an intramolecular N—H...O hydrogen bond, which generates an S(6) ring motif. In the crystal, inversion dimers linked by pairs of C—H...O hydrogen bonds generate R22(16) ring motifs. The dimers are further connected by N—H...N hydrogen bonds, thereby forming layers lying parallel to the bc plane.