(E)-2-[(2-Formylphenoxy)methyl]-3-(4-methylphenyl)prop-2-enenitrile

In the title compound, C18H15NO2, the dihedral angle between the two benzene rings is 74.8 (1)°. The carbonitrile chain is almost linear, the C—C—N angle being 176.2 (2)°. In the crystal, π–π interactions [centroid–centroid distance = 3.842 (1) Å] are observed.

In the title compound, C 18 H 15 NO 2 , the dihedral angle between the two benzene rings is 74.8 (1) . The carbonitrile chain is almost linear, the C-C-N angle being 176.2 (2) . In the crystal,interactions [centroid-centroid distance = 3.842 (1) Å ] are observed.

Comment
The title compound is a stereodefined trisubstituted olefin, synthesized from the corresponding bromoderivative of a Baylis-Hillman adduct with salicylaldehyde via simple SN 2 reaction in good yields. This o-salicyladehyde derivative is an important precursor for many heterocyclic frameworks (Bakthadoss et al., 2010).
The title compound comprises a benzaldehyde moiety connected to a tolyl ring through a chain formed by a methoxy methyl and a propenenitrile group. The X-ray analysis confirms the molecular structure and atom connectivity as illustrated in Fig.1.

Experimental
A solution of salicylaldehyde (1.0 mmol, 0.12 g) and potassium carbonate (1.5 mmol, 0.207 g) in acetonitrile was stirred for 15 minutes at room temperature. To this solution, (E)-2-(bromomethyl)-3-(4-methylphenyl)prop-2-enenitrile (1.2 mmol, 0.28 g) was added dropwise till the addition is complete. After the completion of the reaction, as indicated by TLC, acetonitrile was evaporated. EtOAc (15 ml) and water (15 ml) were added to the crude mass. The organic layer was dried over anhydrous sodium sulfate. Removal of solvent led to a crude product, which was purified through a pad of silica gel (100-200 mesh) using ethylacetate and hexanes (1:9) as solvents. The pure title compound was obtained as a colourless solid (0.24 g, 86 % yield). Recrystallization was carried out using ethylacetate as the solvent.

Refinement
H atoms were positioned geometrically, with C-H = 0.93-0.97 Å and constrained to ride on their parent atom, with U iso (H) =1.5U eq for methyl H atoms and 1.2U eq (C) for the other H atoms.

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.