3,4-Dimethylphenyl quinoline-2-carboxylate

In the title compound, C18H15NO2, the dihedral angle between the mean planes of the quinoline ring system and the phenyl ring is 48.1 (5)°. The mean plane of the carboxylate group is twisted from the mean planes of the latter by 19.8 (8) and 64.9 (5)°, respectively. The crystal packing features weak C—H⋯O interactions, which form chains along [010].

In the title compound, C 18 H 15 NO 2 , the dihedral angle between the mean planes of the quinoline ring system and the phenyl ring is 48.1 (5) . The mean plane of the carboxylate group is twisted from the mean planes of the latter by 19.8 (8) and 64.9 (5) , respectively. The crystal packing features weak C-HÁ Á ÁO interactions, which form chains along [010].
In the title compound, C 18 H 15 NO 2 , the dihedral angle between the mean planes of the quinoline ring and the phenyl ring is 48.1 (5)° (Fig. 1). The mean plane of the carboxylate group is twisted from the mean planes of the quinoline ring and phenyl ring by 19.8 (8)° and 64.9 (5)°, respectively. The crystal packing is influenced by weak C8-H8···O1 intermolecular interactions making chains along [0 1 0] (Fig. 2). No classical hydrogen bonds were observed.

Experimental
The title compound was prepared by the following procedure: To a mixture of 1.73 g (10 mmole) of quinaldic acid and 1.56 g (10 mmole) of 3,4-dimethylphenol in a round-bottomed flask fitted with a reflex condenser with a drying tube is added 0.15 g (10 mmole) of phosphorous oxychloride. The mixture is heated with occasional swirling, and temperature is maintained at 348-353 K. At the end of eight hours the reaction mixture is poured in to a solution of 2 g of sodium bicarbonate in 25 mL of water. The precipitated ester is collected on a filter and washed with water. The yield of crude, air dried 3,4-dimethyl phenyl quinoline-2-carboxylate is 1.47 to 1.90 g (50-65%). X-ray quality crystal was obtained by recrystallization from absolute ethanol.(M.P.:397 K)

Refinement
All of the H atoms were placed in their calculated positions and then refined using the riding model with Atom-H lengths of 0.93Å (CH) or 0.96Å (CH 3 ). Isotropic displacement parameters for these atoms were set to 1.2 (CH) or 1.5 (CH 3 ) times U eq of the parent atom. Idealised Me refined as rotating group.

Figure 1
ORTEP drawing of (I) (C 18 H 15 NO 2 ) showing the labeling scheme with 50% probability displacement ellipsoids.  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.