A second monoclinic polymorph of 2-[2-(4-meth-oxy-phen-yl)hydrazinyl-idene] -1,3-diphenyl-propane-1,3-dione

The title compound, C ₂₂H ₁₈N ₂O ₃ is the second monoclinic polymorph (P21/c) of the compound, the first being reported in space group P21 [Bertolasi et al. (1993). J. Chem. Soc. Perkin Trans. 2, pp. 2223-2228]. In the mol-ecular structure of the title compound, the inter-planar angle between the benzoyl units is 80.04 (5)°, while the corresponding angles between the phenyl-hydrazinyl-idene and benzoyl groups are 36.11 (5) and 55.77 (2)°. A strong resonance-assisted intra-molecular N - H⋯O hydrogen bond is found. In the crystal, the entire supra-molecular structure is constructed by weak inter-molecular C - H⋯O inter-actions and an inter-ring π-π inter-action [centroid-centroid distance = 3.6088 (8) Å].