1-(2-Naphthyl)-3-phenylprop-2-en-1-one

The title compound, C19H14O, contains two independent molecules with the same s-cis conformation for the ketone unit. Both molecules are non-planar with dihedral angles of 51.9 (1) and 48.0 (1)° between the benzene ring and the naphthalene ring system. In the crystal, neighboring molecules are stabilized by intermolecular C—H⋯π interactions, giving a two-dimensional supramolecular array parallel to the ab plane.

The title compound, C 19 H 14 O, contains two independent molecules with the same s-cis conformation for the ketone unit. Both molecules are non-planar with dihedral angles of 51.9 (1) and 48.0 (1) between the benzene ring and the naphthalene ring system. In the crystal, neighboring molecules are stabilized by intermolecular C-HÁ Á Á interactions, giving a two-dimensional supramolecular array parallel to the ab plane.

Comment
Chalcone and its analogues have been extensively researched because of their facile synthesis and potential applications as excellent non-linear optical materials (Agrinskaya et al., 1999;Indira et al., 2002) and biological activities (Opletalova, 2000;Pandey et al., 2005). Ongoing our efforts on the research of chalcone compounds (Tang et al., 2008), a new compound was here presented.
As shown in Fig.1, the title molecule contains two independent and isostructural molecules, which are non-planar because of the serious tilts between the benzene and naphthalene rings of 51.9 (1) ° and 48.0 (1) ° dihedral angles, respectively. In the two molecules, the ketone units display the same s-cis. conformations with the torsion angles of 14.7 (3) ° and 12.3 (3)°, respectively. Meanwhile, the intramolecular C-H···O hydrogen bonds exist within the ketone units, which are also found in the other similar structures (Moorthi et al., 2005;Tang et al., 2008).
In the crystal structure, as shown in Fig.2, neighboring molecules are stacked into a two-dimensional supramolecular layer by intermolecular C-H···π interactions parallel to the ab plane.

Refinement
All H-atoms were positioned geometrically and refined using a riding model with d(C-H) = 0.93 Å, U iso =1.2U eq (C). Fig. 1. The title molecule with displacement ellipsoids drawn at the 30% probability level, and H atoms as spheres of arbitrary radius.

Special details
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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.