1-(3,5-Dimethoxyphenyl)-4,5-dimethyl-2-phenyl-1H-imidazole

In the title molecule, C19H20N2O2, the imidazole ring makes dihedral angles of 57.29 (5) and 31.54 (5)° with the attached dimethoxyphenyl residue and the phenyl ring, respectively. The dihedral angle between the dimethoxyphenyl and phenyl rings is 61.15 (5)°. In the crystal, pairs of C—H⋯N hydrogen bonds connect the molecules into inversion dimers.

In the title molecule, C 19 H 20 N 2 O 2 , the imidazole ring makes dihedral angles of 57.29 (5) and 31.54 (5) with the attached dimethoxyphenyl residue and the phenyl ring, respectively. The dihedral angle between the dimethoxyphenyl and phenyl rings is 61.15 (5) . In the crystal, pairs of C-HÁ Á ÁN hydrogen bonds connect the molecules into inversion dimers.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT6926).

Comment
The title compound was synthesized in an attempt to develop highly sensitive chemosensors for transition metal ions.
Similar compounds have the potential to be used as a ligand for synthesizing Ir 3+ complexes (Saravanan et al., 2011;Gayathri et al., 2010). Imidazole derivatives are found to have diverse activities like anti-inflammatory and antimicrobial activity (Zala et al., 2012).
In the title molecule ( Fig.1), the imidazole ring makes dihedral angles of 57.29 (5)° and 31.54 (5)° with the attached dimethoxyphenyl residue and the phenyl ring, respectively. The dihedral angle between the benzene and phenyl rings is 61.15 (5)°. Two inversion related molecules (Table 1) connected by C-H···N hydrogen bonds form a centrosymmetric dimer (Fig. 2).

Experimental
To pure biacetyl (1.48 g, 15 mmol) in ethanol (10 ml), 3,5 dimethoxyaniline (2.30 g,15 mmol), ammonium acetate(7.0 g, 15 mmol) and benzaldehyde (1.5 g 15 mmol) were added for a period of about one hour by maintaining the temperature at 333 K. The reaction mixture was refluxed for five days and extracted with dichloromethane. The solid which separated was purified by column chromatography using hexane:ethyl acetate as the eluent. Yield: 2.1 g (45%).

Refinement
The positions of all the hydrogen atoms were identified from a difference electron density map. Nevertheless, hydrogen atoms were placed in calculated positions with distances C-H ranging from 0.93 to 0.96 Å and refined using a riding model with U iso (H) = 1.5 U eq (C) for methyl groups and U iso (H) = 1.2 U eq (C) for the remaining H atoms.

Computing details
Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 and SAINT (Bruker, 2004); data reduction: SAINT and XPREP (Bruker, 2004); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: PLATON (Spek, 2009  The molecular structure of the title compound,with displacement ellipsoids drawn at the 50% probability level·H atoms are shown as small sphere of arbitrary radius.  The packing of the title compound,viewed down the c axis; dashed lines indicates hydrogen bonds. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.22 e Å −3 Δρ min = −0.17 e Å −3 Extinction correction: SHELXL97 (Sheldrick, 2008), Fc * =kFc[1+0.001xFc 2 λ 3 /sin(2θ)] -1/4 Extinction coefficient: 0.041 (5) 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.