2-[4-(4,5-Dihydro-1H-pyrrol-2-yl)phenyl]-4,5-dihydro-1H-imidazole

The molecule of the title compound, C12H14N4, lies about a crystallographic inversion centre. The five- and six-membered rings are twisted from each other, forming a dihedral angle of 18.06 (7)°. In the crystal structure, neighbouring molecules are linked by intermolecular N—H⋯N hydrogen bonds into one-dimensional infinite chains forming 18-membered rings with R 2 2(18) motifs. The crystal structure is further stabilized by weak intermolecular π–π stacking [centroid–centroid distance = 3.8254 (6) Å] and C—H⋯π interactions.

The molecule of the title compound, C 12 H 14 N 4 , lies about a crystallographic inversion centre. The five-and six-membered rings are twisted from each other, forming a dihedral angle of 18.06 (7) . In the crystal structure, neighbouring molecules are linked by intermolecular N-HÁ Á ÁN hydrogen bonds into onedimensional infinite chains forming 18-membered rings with R 2 2 (18) motifs. The crystal structure is further stabilized by weak intermolecularstacking [centroid-centroid distance = 3.8254 (6) Å ] and C-HÁ Á Á interactions.

Comment
Imidazoline derivatives are of great importance because they exhibit significant biological and pharmacological activities including anti-hypertensive (Blancafort 1978), anti-hyperglycemic (Chan 1993), anti-depressive (Vizi 1986), anti-hypercholesterolemic (Li et al., 1996) and anti-inflammatory (Ueno et al., 1995) activities. These compounds are also used as catalysts and synthetic intermediates in some organic reactions (Corey & Grogan 1999). In consideration of the important applications of imidazolines, herein the crystal structure of the title compound, (I), is reported.
In compound (I), Fig. 1, bond lengths and angles are within the normal ranges and are comparable with a related structure (Stibrany et al., 2004). The molecule lies about a crystallographic inversion centre. The five-and six-membered rings are twisted from each other, forming a dihedral angle of 18.06 (7)°. Intermolecular N-H···N hydrogen bonds form 18membered rings producing R 2 2 (18) ring motifs to link molecules into one-dimensional infinite chains along the b-axis, Table   1 and Fig. 2. The crystal structure is further stabilized by weak intermolecular π-π stacking [Cg1···Cg2 i = 3.8254 (6) Å; (i) 1 + x, y, z] and C-H···π (Cg1 and Cg2 are the centroids of the N1/C1/C2/N2/C3 imidazoline ring and the benzene ring, respectively) interactions, Table 1.

Experimental
The synthetic method used for the preparation of (I) was based on previous work (Stibrany et al. 2004), except that 1,4-dicyanobenzene (10 mmol) and ethylenediamine (40 mmol) were used. Single crystals suitable for X-ray diffraction were obtained by evaporation of a methanol solution of (I) held at room temperature.

Refinement
All hydrogen atoms were located from a difference Fourier map and refined freely: C-H ranged from 0.961 (16) to 1.015 (15) Å and N-H was 0.874 (18) Å. Fig. 1. The molecular structure of (I) with atom labels and 50% probability ellipsoids for non-H atoms. Unlabelled atoms are related by -x + 1, -y, -z.

Special details
Experimental. The low-temperature data was collected with the Oxford Cyrosystem Cobra low-temperature attachment.
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 mat-