title: Crystal structure of (4Z)-4-[(2E)-3-(2-chloro-phen-yl)-1-hy-droxy-prop-2-en-1-yl-idene]-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one.
abstract: In the title compound, C19H15ClN2O2, the pyrazole ring is almost planar (r.m.s. deviation = 0.002 Å) and subtends dihedral angles of 5.31 (16) and 1.86 (16)° with the phenyl and chloro-benzene rings, respectively. An intra-molecular O-H⋯O hydrogen bond closes an S(6) ring and a short C-H⋯O contact is also observed. In the crystal, mol-ecules are linked by weak C-H⋯O inter-actions to generate (001) sheets. Weak aromatic π-π inter-actions between the chloro-benzene and pyrazole rings, with a centroid-centroid distance of 3.7956 (17) Å are also observed.
authors.affiliation: Department of Chemistry, University of the Punjab, Lahore, Punjab, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Shahid
authors.affiliation: Department of Chemistry, University of the Punjab, Lahore, Punjab, Pakistan.
authors.forename: Munawar Ali
authors.initials: MA
authors.lastname: Munawar
authors.affiliation: Department of Physics, University of Sargodha, Sargodha, Punjab, Pakistan.
authors.forename: Muhammad Nawaz
authors.initials: MN
authors.lastname: Tahir
authors.affiliation: Department of Chemistry, University of the Punjab, Lahore, Punjab, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Salim
authors.affiliation: Department of Chemistry, University of the Punjab, Lahore, Punjab, Pakistan.
authors.forename: Khizar Iqbal
authors.initials: KI
authors.lastname: Malik
keywords: crystal structure; hydrogen bonding; pyrazole; π–π inter­actions