4-Chloro-6-methyl-N-(4-methylphenyl)quinolin-2-amine

In the title compound C17H15ClN2, the dihedral angle between the quinoline ring system and the phenyl ring is 50.18 (6)°. In the crystal, molecules are linked into chains running along the c axis by N—H⋯N hydrogen bonds.

In the title compound C 17 H 15 ClN 2 , the dihedral angle between the quinoline ring system and the phenyl ring is 50.18 (6) . In the crystal, molecules are linked into chains running along the c axis by N-HÁ Á ÁN hydrogen bonds.
Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009  analogs have attractive profile and are a good start point to initiate a lead optimisation programme. Due to its significant biological importance, the title compound was chosen for the X-ray crystallographic study.
The title compound is the first structural example with methyl phenyl moiety attached to the amino substituted quinoline.
The chlorine atom deviates only by 0.0276 (5)Å below the mean plane of atoms passing through C2-C10, N1. The methyl phenyl moiety is oriented at 129.9 (5)° from the plane containing the quinoline ring system. C-H···N and N-H···N intermolecular interactions assist the molecular packing of the crystal which resembles helical patterns. In addition to van der Waals forces, the hydrogen bond interactions at the groove of helix maintains the stability of the crystal packing. Atom N1 acts as a bifurcated acceptor. The bifurcated hydrogen bond also forms the R 1 2 (6) motif.
The structure of the title compound is shown in Figure 1. All the bond lengths and bond angles are in the usual ranges. The molecular packing with hydrogen bonds as dotted lines is shown in Figure 2.

Experimental
A mixture of appropriate 6-methyl-2,4-dichloroquinoline (0.010 mol) and p-toluidine (0.010 mol) was heated under neat condition at 160°C for half an hour. The product obtained was washed with water, dried and purified by column chromatography over silica gel and eluted with petroleum ether : ethyl acetate mixture (99 : 1) to get the product as pale yellow solid. It was recrystallised using methanol.

Refinement
The H-atoms were positioned geometrically and treated as riding atoms: C-H =0.93 Å H-aromatic, C-H = 0.96 Å Hmethyl, and N-H = 0.86 Å, with U iso = k×U eq (parent C or N-atom), where k = 1.5 for methyl H-atoms, and = 1.2 for all 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.