(E)-1-(4-Nitrophenyl)-3-phenylprop-2-en-1-one

In the title compound, C15H11NO3, the configuration of the keto group with respect to the olefinic double bond is s–cis. The two benzene rings form a dihedral angle of 5.00 (5)°. The molecules are linked into a two-dimensional network parallel to (04) by C—H⋯O hydrogen bonds.

In the title compound, C 15 H 11 NO 3 , the configuration of the keto group with respect to the olefinic double bond is s-cis. The two benzene rings form a dihedral angle of 5.00 (5) . The molecules are linked into a two-dimensional network parallel to (104) by C-HÁ Á ÁO hydrogen bonds.

S1. Comment
Chalcone derivatives are a class of important compounds that possess antiprotzoal, antihelmintic, amoebicidal, anti-ulcer, antiviral, insecticidal, antibacterial, anticancer, cytotoxic and immunosuppressive activities (Dimmock et al., 1999). The crystal structures of some chalcone derivatives have been reported. We report here the crystal structure of the title compound.
Bond lengths and angles in the title molecule are normal. The configuration of the keto group with respect to the olefinic double bond is typically s-cis, with a O1-C9-C8-C7 torsion angle of 0.5 (2)° ( Fig. 1). The N1/O2/O3 and C10-C15 planes form a dihedral angle of 10.80 (11)°. The two benzene rings (C10-C15 and C1-C6) form a dihedral angle of 5.00 (5)°. The crystal packing is stabilized by C-H···O hydrogen bonds (Table 1). The molecules are linked into a two-dimensional network parallel to the (1 0 4) by the above hydrogen bonds.

S2. Experimental
The title compound was synthesized according to the method reported in the literature (Cocconcelli et al., 2008). Yellow single crystals suitable for X-ray diffraction were obtained by slow evaporation of a acetone solution.

S3. Refinement
All H atoms were placed in calculated positions, with C-H = 0.95 Å, and refined using a riding model, with U iso (H) = 1.2U eq (C).  The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atomic numbering.

Special details
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.