Crystal structure of (Z)-4-[1-(4-acetylanilino)ethyl-idene]-3-methyl-1-phenyl-1 H-pyrazol-5(4H)-one

Abstract

In the solid state, the title compound, C20H19N3O2, adopts the keto-amine tautomeric form, with the H atom attached to the N atom, which participates in an intramolecular N - H⋯O hydrogen bond with an S(6) ring motif. The dihedral angles between the pyrazole ring and the phenyl and benzene rings are 3.69 (10) and 46.47 (9)°, respectively. In the crystal, molecules are linked by weak C - H⋯O hydrogen bonds, generating C(16) chains propagating in [301]. Weak aromatic π-π stacking interactions [centroid-centroid distances = 3.6123 (10) and 3.6665 (10) Å] link the chains into a three-dimensional network.