3-(1H-1,3-Benzimidazol-2-yl)-2,7-dimethoxyquinoline

In the title molecule, C18H15N3O2, the dihedral angle between the quinoline and benzimidazole ring systems is 23.57 (5)°. The C atoms of the methoxy groups are both close to being coplanar with their attached ring systems [deviations = 0.193 (2) and −0.020 (2) Å]. An intramolecular N—H⋯O hydrogen bond closes an S(6) ring. In the crystal, N—H⋯N hydrogen bonds link the molecules into C(4) chains propagating in [010]. Weak C—H⋯π interactions also occur.

In the title molecule, C 18 H 15 N 3 O 2 , the dihedral angle between the quinoline and benzimidazole ring systems is 23.57 (5) . The C atoms of the methoxy groups are both close to being coplanar with their attached ring systems [deviations = 0.193 (2) and À0.020 (2) Å ]. An intramolecular N-HÁ Á ÁO hydrogen bond closes an S(6) ring. In the crystal, N-HÁ Á ÁN hydrogen bonds link the molecules into C(4) chains propagating in [010]. Weak C-HÁ Á Á interactions also occur.

Comment
In the course of our program related to the synthesis of new suitably functionalized heterocyclic compounds of potential biological activity, (Benzerka et al., 2012;Hayour et al., 2011), we now report herein the synthesis and structure determination of the title compound, C 18 H 15 N 3 O 2 . The reactivity of this compound and its analogues toward nucleophiles is under investigation.
The molecular geometry and the atom-numbering scheme of (I) are shown in Fig. 1. In the asymmetric unit of title compound the dimethoxyquinoline unit bearing an benzo imidazol moiety. The two rings of quinolyl moiety are fused in an axial fashion and form a dihedral angle of 2.68 (4)°. The heterocycle ring of quinolyl unit form also with imidazol plane a dihedral angle of 24.09 (5)°. The crystal packing can be described as layers in zig zag parallel to (010) plane, along the c axis (Fig. 2). It is stabilized by intra and intermolecular hydrogen bond (N-H···N and N-H···O) and C-H···π stacking, resulting in the formation of infinite three-dimensional network linked these layers toghter and reinforcing a cohesion of structure. Hydrogen-bonding parameters are listed in table 1.

Refinement
All non-H atoms were refined with anisotropic atomic displacement parameters. All H atoms were localized on Fourier maps but introduced in calculated positions and treated as riding on their parent C or N atom. (with C-H = 0.95 and 0.98 Å, N-H = 0.88 Å and U iso (H) =1.5 or 1.2(carrier atom)).

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