6-(4-Aminophenyl)-2-methoxy-4-phenylnicotinonitrile

In the structure of the title nicotinonitrile derivative, C19H15N3O, the pyridine ring makes dihedral angles of 11.50 (7) and 43.36 (8)° with the 4-aminophenyl and phenyl rings, respectively, and the dihedral angle between the phenyl rings is 36.28°. In the crystal, molecules are linked by N—H⋯N hydrogen bonds into wave-like sheets parallel to (10-2). These sheets are stacked by π–π interactions between the 4-aminophenyl rings of adjacent sheets, with centroid–centroid distances of 3.7499 (9) Å. C—H⋯π interactions are also present.

The title compound (I), C 19 H 15 N 3 O, is a non-planar molecule (Fig. 1). The pyridine ring makes dihedral angles of 11.50 (7)° and 43.36 (8)° with the 4-aminophenyl and phenyl rings, respectively, and the dihedral angle between the two phenyl rings is 36.28°. The methoxy group lies in the plane of the pyridine ring with an rms deviation of 0.0102 (1) Å for the eight non-H atoms (C7-C9/C16-C17/C19/N2/O1) and the torsion angle C19-O1-C16-N2 = -1.2 (2)°. The cyano group is also roughly co-planar with the pyridine ring with an rms deviation of 0.0406 (1) Å from the ring plane. The bond distances in (I) agree with the literature values (Allen et al., 1987) and are comparable to those found in closely related structures Suwunwong et al., 2012;.

Experimental
The title compound (I) was synthesized by stirring a solution of (E)-1-(4-aminophenyl)-3-phenylprop-2-en-1-one (0.22 g, 1 mmol) in methanol (10 ml) with freshly prepared sodium methoxide (1.0 mmol of sodium in 20 ml of methanol). An excess of malononitrile (0.13 g, 2 mmol) was then added with continuous stirring at room temperature until a precipitate was obtained. The resulting solid was filtered. Yellow plate-shaped single crystals of the title compound suitable for X-ray structure determination was recrystallized from ethanol/methanol (1:1 v/v) by slow evaporation of the solvent at room temperature over several days. Mp. 475-476 K.

Refinement
The amino H atoms were located from difference maps and refined isotropically. The remaining H atoms were positioned geometrically and allowed to ride on their parent atoms, with d(C-H) = 0.95 Å for aromatic and 0.98 Å for CH 3 atoms.

sup-2
Acta Cryst. (2013). E69, o1816-o1817 The U iso values were constrained to be 1.5U eq of the carrier atom for methyl H atoms and 1.2U eq for the remaining H atoms. A rotating group model was used for the methyl groups.

Figure 1
The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom-numbering scheme. Wave-like sheets of the title compound viewed approximately along the a axis. N-H···N hydrogen bonds are shown as dashed lines.  (Cosier & Glazer, 1986) operating at 100.0 (1) K. 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.