2-[2-(4-Methoxyphenyl)-4,5-diphenyl-1H-imidazol-1-yl]ethanol

In the title compound, C24H22N2O2, the central imidazole ring makes dihedral angles of 49.45 (8), 88.94 (9) and 19.43 (8)° with the benzene ring and the two phenyl rings, respectively. The dihedral angle between the phenyl rings is 77.86 (9)°, and they form dihedral angles of 49.06 (9) and 67.31 (8)° with the benzene ring. In the crystal, molecules are linked by O—H⋯N hydrogen bonds, forming chains along the b axis. These chains are connected by C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (100). In addition, C—H⋯π interactions are also observed. The terminal C and O atoms of the ethanol group are disordered over two sets of sites with an occupancy ratio of 0.801 (5):0.199 (5).

In the title compound, C 24 H 22 N 2 O 2 , the central imidazole ring makes dihedral angles of 49.45 (8), 88.94 (9) and 19.43 (8) with the benzene ring and the two phenyl rings, respectively. The dihedral angle between the phenyl rings is 77.86 (9) , and they form dihedral angles of 49.06 (9) and 67.31 (8) with the benzene ring. In the crystal, molecules are linked by O-HÁ Á ÁN hydrogen bonds, forming chains along the b axis. These chains are connected by C-HÁ Á ÁO hydrogen bonds, forming a two-dimensional network parallel to (100). In addition, C-HÁ Á Á interactions are also observed. The terminal C and O atoms of the ethanol group are disordered over two sets of sites with an occupancy ratio of 0.801 (5):0.199 (5).

Experimental
Cg1 is the centroid of the C4-C9 benzene ring.

Gurbanov Comment
Heterocyclic compounds such as imidazoles have been a traditional focal point for the development of new bio-active molecules such as anticancer agents (Krezel, 1998;Andreani et al. 2000). Many of the substituted imidazoles are known as inhibitors of fungicides and herbicides, plant growth regulators and therapeutic agents (Maier et al. 1989a,b). As part of our on-going study to develop new routes for synthesis of tetra-substituted imidazole based amino alcohol compounds, we herein report the synthesis and crystal structure of the title compound.
In the crystal, O-H···N hydrogen bonds (Table 1 and Fig 2) connect the molecules to form chains along the b axis direction. These chains are linked by C-H···O hydrogen bonds forming a two-dimensional network parallel to the bc plane. There are also C-H···π interactions present (Table 1).

Experimental
A mixture of 2.1 g (10 mmol) 1,2-diphenylethane-1,2-dione, 1.36 g (10 mmol) 4-methoxybenzaldehyde, 0.67 g (11 mmol) 2-aminoethanol and 0.77 g (10 mmol) ammonium acetate was added to 0.5 g (3 mmol) of a fresh prepared diethyl ammonium hydrogen sulfate as an ionic liquid. The reaction mixture was heated on oil bath at 373 K and monitored by TLC till completion after 30 min then poured on water. The obtained solid was filtered off, washed with cold ethanol and dried under vacuum. The crude product was crystallized from ethanol to afford colourless prisms (m.p. 460 -462 K), by slow evaporation at room temperature, in excellent yield (95%).

Figure 1
A view of the molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.   Table 1 for details). H atoms not involved in hydrogen bonding have been omitted for clarity. Special details Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles Refinement. Refinement on F 2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses 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 observed criterion of F 2 > σ(F 2 ) is used only for calculating -R-factor-obs 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.