2-(4-Methoxyphenyl)-4,5-dihydro-1H-imidazole

In the title molecule, C10H12N2O, the dihedral angle between the benzene and imidazole rings is 14.86 (16)°. The approximately planar arrangement of the molecule results in a distance of 2.54 Å between an ortho-H atom of the benzene ring and the double-bonded N atom of the imidazole ring. In the crystal structure, symmetry-related molecules are linked by intermolecular N—H⋯N hydrogen bonds into one-dimensional chains extending along the a axis.


Comment
Imidazoline derivatives are of great importance because they exhibit significant biological and pharmacological activities such as antihypertensive (Blancafort 1978), antihyperglycemic (Chan 1993), antidepressive (Vizi 1986), antihypercholesterolemic (Li et al., 1996) and anti-inflammatory (Ueno et al., 1995) properties. These compounds are also used as catalysts and synthetic intermediates in some organic reactions (Corey & Grogan 1999). With regards to these important applications of imidazolines, herein we report the crystal structure of the title compound, (I).
In the title compound (I, Fig. 1), bond lengths (Allen et al. 1987) and angles are with the normal ranges and are comparable with the related structures (Stibrany et al. 2004;Kia et al., 2008Kia et al., , 2009a. The molecule is approximately planar with a maximum deviation from the mean plane of the molecule for atom N1 being 0.279 (2) Å. The six-and five-membered rings are twisted from each other, forming the dihedral angle of 14.86 (16)°. Atom H5A of the benzene ring is in close proximity to atom N2 atom of the imidazoline ring with a distance of 2.54 Å [N2···H5A]. In the crystal structure, neighbouring molecules are linked together by intermolecular N-H···N hydrogen bonds into 1-D extended chains along the a axis (Table 1, Fig. 2).

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

Refinement
The N-bound hydrogen atom was located from the difference Fourier map are refined freely, see Table. 1. The rest of the hydrogen atoms were positioned geometrically with a riding approximation model with C-H = 0.95-0.99 Å and U iso (H) = 1.2 & 1.5 U eq (C). A rotating group model was applied for the methyl group. In the absence of significant anomalous dispersion effects, 943 Friedel pairs were merged before the final refinement. Fig. 1. The molecular structure of the title compound with atom labels and 50% probability ellipsoids for non-H atoms.

Special details
Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K. 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 Rfactors(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.