3-Anilino-1,3-di-2-pyridylpropan-1-one

The title compound, C19H17N3O, was prepared by the 1,4-addition reaction of 1,3-di-2-pyridylprop-2-en-1-one with aniline, and includes one chiral C atom of the methine group with an R configuration. The crystal structure is stabilized by intermolecular N—H⋯N and C—H⋯O hydrogen bonds. The crystal structure also exhibits weak intermolecular C—H⋯π interactions between a pyridyl H atom and the phenyl ring of adjacent molecules.

The title compound, C 19 H 17 N 3 O, was prepared by the 1,4addition reaction of 1,3-di-2-pyridylprop-2-en-1-one with aniline, and includes one chiral C atom of the methine group with an R configuration. The crystal structure is stabilized by intermolecular N-HÁ Á ÁN and C-HÁ Á ÁO hydrogen bonds. The crystal structure also exhibits weak intermolecular C-HÁ Á Á interactions between a pyridyl H atom and the phenyl ring of adjacent molecules.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: LX2115).

Comment
The binucleating ligand has continued to arouse interest among chemists, because the extensive investigation of binucleating ligands plays a key role in bimetallic chemistry. These coordination compounds were potentially applied in bioinorganic chemistry, homogeneous catalysis, magnetic exchange processes, and information of performance on important enzymes (Lam et al., 1996, Clare et al., 2004& Casalino et al., 2009. Furthermore, compounds comprising multiple pyridyl groups are widely used in the design and self-assembly of metal-organic architectures (Huang et al., 2008). Here we report the crystal structure of title compound (I) (Fig. 1).
The bond distances and angles in (I) are consistent with the values in related structures (Champouret et al., 2006& Murthy et al., 2001. The chiral C8 atom possesses the expected R configuaration. The molecualr packing ( Fig. 2) is stabiized by intermolecular N-H···N and C-H···O hydrogen bonds; the first between the amino H atom and the pyridyl (C9-C13/N2) N atom, with a N3-H3···N2 i , the second between the pyridyl (C9-C13/N2) H atom and the oxygen of the C═O unit, with a C10-H10···O1 i , respectively (Table 1). The crystal packing (Fig. 3) is further stabilized by intermolecular C-H···π interactions between the pyridyl (C1-C5/N1) H atom and the phenyl ring, with a C3-H3···Cg ii (Table 1; Cg is the centroid of the C14-C19 phenyl ring).

Experimental
1,3-di-2-pyridyl-2-en-1-one (5 mmol/1.044 g) was mixed with aniline (6 mmol/0.558 g) in toluene (20 ml). And then the phosphotungsitic (0.01 g) in water (10 ml) was added dropwise and refluxed for 2 h. The insoluble materials were produced, and then removed by filtration. The organic layer was kept at room temperature for about two days. Yellow-colored and block shaped crystals were collected (yield 67.6%).

Refinement
All the Friedel pairs were merged. H atoms were positioned geometrically and allowed to ride on their parent atoms, with N-H and C-H distances of 0.86 and 0.93-0.96 Å, respectively, and with U iso (H) = 1.2U eq of the parent atoms. Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as a small cycles 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.