1-{2-Phenyl-2-[4-(trifluoromethyl)benzyloxy]ethyl}-1H-benzimidazole

The asymmetric unit of the crystal structure of the title compound, C23H19F3N2O, contains two independent molecules. In the two molecules the planar benzimidazole ring systems are oriented with respect to the phenyl/trifluoromethylbenzene rings at dihedral angles of 9.62 (6)/78.63 (7) and 2.53 (8)/83.83 (9)°. In the crystal structure, intermolecular C—H⋯N hydrogen bonds link the molecules into R 2 2(6) dimers. The molecules are elongated along [001] and stacked along the b axis.

The asymmetric unit of the crystal structure of the title compound, C 23 H 19 F 3 N 2 O, contains two independent molecules. In the two molecules the planar benzimidazole ring systems are oriented with respect to the phenyl/trifluoromethylbenzene rings at dihedral angles of 9.62 (6)/78.63 (7) and 2.53 (8)/83.83 (9) . In the crystal structure, intermolecular C-HÁ Á ÁN hydrogen bonds link the molecules into R 2 2 (6) dimers. The molecules are elongated along [001] and stacked along the b axis.

Comment
In recent years, there has been increasing interest in synthesis of heterocyclic compounds having biological and commercial importances. Clotrimazole (Song & Shin, 1998), econazole (Freer et al., 1986), ketoconazole (Peeters et al., 1979a and miconazole (Peeters et al., 1979b) are well known imidazole ring containing, while itraconazole (Peeters et al., 1996) and fluconazole (Caira et al., 2004) are 1H-1,2,4-triazole ring containing, azole derivatives. They have been developed for clinical uses as antifungal agents (Brammer & Feczko, 1988). Lately, similar structures to miconazole and econazole have been reported to show antibacterial activity more than antifungal activity (Özel Güven et al., 2007a,b). In these structures, benzimidazole ring has been found in place of the imidazole ring of miconazole and econazole. Recently, we reported the crystal structures of furyl (Özel Güven et al., 2008a) and phenyl (Özel Güven et al., 2008b) substituted compounds, and we report herein the crystal structure of title benzimidazole derivative.
In the crystal structure, intermolecular C-H···N hydrogen bonds (Table 1) link the molecules to form a R 2 2 (6) ring motif (Bernstein et al., 1995), in which they may be effective in the stabilization of the structure. The molecules are elongated along [001], and stacked along the b axis (Fig. 2).

Experimental
The title compound was synthesized by the reaction of 2-(1H-benzimidazol-1-yl)-1-phenylethanol (Özel Güven et al., 2007a) with NaH and appropriate benzyl halide. To the solution of alcohol (300 mg, 1.259 mmol) in DMF (2.4 ml) was added NaH (63 mg, 1.574 mmol) in small fractions. The appropriate benzyl halide (300 mg, 1.259 mmol) in DMF (1.2 ml) was added dropwise. The mixture was stirred at room temperature for 2 h and excess hydride was decomposed with a small amount of methyl alcohol. After evaporation to dryness under reduced pressure, the crude residue was suspended with water and extracted with methylene chloride. The organic layer was dried over anhydrous sodium sulfate, and then evaporated to dryness. The crude residue was purified by chromatography on a silica-gel column using chloroform-methanol as eluent.
Crystals suitable for X-ray analysis were obtained by the recrystallization of the ether from a mixture of hexane/ethyl acetate (1:2) (yield; 296 mg, 59%).
supplementary materials sup-2 Refinement H atoms were positioned geometrically, with C-H = 0.93, 0.98 and 0.97 Å for aromatic, methine and methylene H, respectively, and constrained to ride on their parent atoms with U iso (H) = 1.2U eq (C). Fig. 1. The molecular structure of the title molecule with the atom-numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.