(2E)-3-(2-Chloro-7-methylquinolin-3-yl)-1-(6-chloro-2-methyl-4-phenylquinolin-3-yl)prop-2-en-1-one ethanol monosolvate

In the title ethanol solvate, C29H20Cl2N2O·C2H5OH, the quinolinyl residues form a dihedral angle of 46.41 (4)° with each other, and each is inclined [Cp—C—C=O and C=C—C—Cp (p = pyridyl) torsion angles = 54.8 (2) and 144.44 (19)°, respectively] with respect to the almost planar bridging prop-2-en-1-one residue [O=C—C=C torsion angle = −4.1 (3)°]. The ethanol solvent molecule is disordered over two positions of equal occupancy and is located close to a centre of inversion. These molecules reside in cavities defined by the organic molecules, which are connected into a three-dimensional architecture by C—H⋯Cl, C—H⋯O and C—H⋯N interactions, as well as π–π contacts [inter-centroid distances = 3.5853 (10) and 3.8268 (11) Å], each involving pyridyl rings.

In the title ethanol solvate, C 29 H 20 Cl 2 N 2 OÁC 2 H 5 OH, the quinolinyl residues form a dihedral angle of 46.41 (4) with each other, and each is inclined [C p -C-C O and C C-C-C p (p = pyridyl) torsion angles = 54.8 (2) and 144.44 (19) , respectively] with respect to the almost planar bridging prop-2-en-1-one residue [O C-C C torsion angle = À4.1 (3) ]. The ethanol solvent molecule is disordered over two positions of equal occupancy and is located close to a centre of inversion. These molecules reside in cavities defined by the organic molecules, which are connected into a three-dimensional architecture by C-HÁ Á ÁCl, C-HÁ Á ÁO and C-HÁ Á ÁN interactions, as well ascontacts [inter-centroid distances = 3.5853 (10) and 3.8268 (11) Å ], each involving pyridyl rings.   Table 1 Hydrogen-bond geometry (Å , ).

Comment
Quinoline analogues, including chalcones, have gained much attention due to their bio-activities such as anti-bacterial, anti-fungal, anti-malarial and anti-cancer activities (Joshi et al., 2011;Prasath et al., 2013a). It was in this connection that the title compound, (I), was investigated.

Experimental
A mixture of 3-acetyl-6-chloro-2-methyl-4-phenylquinoline (300 mg, 0.001 M) and 2-chloro-7-methylquinoline-3carbaldehyde (200 mg, 0.001 M) in methanol (20 ml) containing potassium hydroxide (0.2 g) was stirred at room temperature for 12 h. Then the reaction mixture was neutralized with dilute acetic acid and the solid that formed was filtered off, washed with distilled ethanol to remove excess of water (from dilute acetic acid), dried and purified by column chromatography using an ethyl acetate-hexane (4:1) mixture to afford compound (I). Re-crystallization was by slow evaporation of its acetone solution, which yielded prisms in 87% yield; M.pt: 453-455 K.

Refinement
Carbon-bound H-atoms were placed in calculated positions [C-H = 0.95-0.98 Å, U iso (H) = 1.2-1.5U eq (C)] and were included in the refinement in the riding model approximation. The oxygen-bound H-atoms were treated similarly with O -H = 0.84 Å, and with U iso (H) = 1.5U eq (O)]. A disordered ethanol molecule of solvation was found towards the final stages of the refinement. Two positions of half-weight were resolved and these are disordered over a centre of inversion.

Figure 1
The molecular structure of (I) showing the atom-labelling scheme and displacement ellipsoids at the 70% probability level. The disordered ethanol molecule is not shown.  View in projection down the c axis of the unit-cell contents of (I). The disordered ethanol molecules, highlighted in space-filling mode, occupy cavities defined by the organic molecules which are connected by C-H···Cl, C-H···O, C-H···N and π-π interactions, shown as green, orange, blue and purple dashed lines, respectively. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.52 e Å −3 Δρ min = −0.77 e Å −3

Special details
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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.