4-(o-Tolylamino)benzaldehyde

In the title compound, C14H13NO, the dihedral angle between the aromatic rings is 49.64 (18)°. The crystal structure is stabilized by N—H⋯O, C—H⋯O and C—H⋯π hydrogen bonds.

In the title compound, C 14 H 13 NO, the dihedral angle between the aromatic rings is 49.64 (18) . The crystal structure is stabilized by N-HÁ Á ÁO, C-HÁ Á ÁO and C-HÁ Á Á hydrogen bonds.

Comment
Diarylamines represent an important class of compounds due to their wide applications and special pharmacological activities (Ohta et al. 2008;Li et al. (2008).). We report here the synthesis and the crystal structure of the title compound, C 14 H 13 NO, which consists of benzaldehyde and tolyl groups attached at the terminal nitrogen atoms (Fig. 1). The dihedral angle between the aromatic rings is 49.64 (18)°. The N1, C14 and H14A atoms are coplanar with the phenyl ring C8 to C13, with deviations of -0.053 (3) Å, -0.076 (4) Å, and -0.07 (1) Å from the ring plane, respectively. The non-planar conformation of the title molecule is not only due to the intramolecular C14-H14A···N1 hydrogen bond, but also owing to the repulsion of H14A and H1 together with packing effects and intermolecular interactions ( Fig. 1 and Table 1).In the crystal, zigzag chains are formed along a through the intermolecular N-H···O and C-H···O hydrogen bonds ( Fig. 2 and Table 1). The molecules are also stabilized by weak C-H···π interactions (Table 1: Cg1 ii is the centroid of the tolyl ring C8 -C13).

Experimental
To a magnetically stirred solution of o-toluidine (1.0 mmol) and Cs 2 CO 3 (3.2 mmol) in dry DMF cooled by ice bath were added chloroacetyl chloride (1.2 mmol) and 4-hydroxybenzaldehyde (1.0 mmol). The reaction mixture was then stirred for 30 min at room temperature and placed into a microwave oven (600 W, 423K) and irradiated for 35 min. The solvent was removed under vacuum and water (20 ml) was added into the residue. The mixture was then extracted by ethyl acetate (4 x 30 ml). The combined organic layers were dried over anhydrous MgSO 4 and evaporated under vacuum to give the crude product, which was purified by column chromatography on silica gel using ethyl acetate/petroleum ether (yield 89%).
Crystals suitable for X-ray diffraction were obtained by slow evaporation of a solution of the solid dissolved in ethyl acetate/petroleum ether at room temperature for 4 days.

Refinement
All H atoms were positioned geometrically and refined using a riding model, with C-H = 0.93 Å for aryl and 0.96 Å for methyl H atoms, and with U iso (H) =1.2U eq (C) for aryl H atoms, and 1.5U eq (C) for methyl H atoms. The C1-and N1-bound H-atoms were located in a difference Fourier map, the U iso values were freely refined. In the absence of significant anomalous dispersion effects, Friedel pairs were averaged. Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.