2-({4-[4-(1H-Benzimidazol-2-yl)phenyl]-1H-1,2,3-triazol-1-yl}methoxy)ethanol

In the title molecule, C18H17N5O2, the dihedral angle between the benzene plane and the benzimidazole plane is 19.8 (1)° and the angle between the benzene plane and the triazole plane is 16.7 (1)°. In the crystal, molecules are connected by O—H⋯N hydrogen bonds, forming zigzag chains along the c-axis direction. The chains are connected by bifurcated N—H⋯(N,N) hydrogen bonds into layers parallel to (100). These layers are connected along the a-axis direction by weak C—H⋯O contacts, forming a three-dimensional network.

In the title molecule, C 18 H 17 N 5 O 2 , the dihedral angle between the benzene plane and the benzimidazole plane is 19.8 (1) and the angle between the benzene plane and the triazole plane is 16.7 (1) . In the crystal, molecules are connected by O-HÁ Á ÁN hydrogen bonds, forming zigzag chains along the caxis direction. The chains are connected by bifurcated N-HÁ Á Á(N,N) hydrogen bonds into layers parallel to (100). These layers are connected along the a-axis direction by weak C-HÁ Á ÁO contacts, forming a three-dimensional network.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: NC2282).
A view of the molecular structure of the title compound is shown in Fig. 1. The molecule contains three planar parts: the benzimidazole, the benzene and the triazole groups. The angle between the benzene and benzimidazole planes is 19.8 (1)°, while the angle between the benzene and triazole planes is 16.7 (1)°. The  Table 1). Adjacent molecules in each chain are related by c-gilde plane symmetry.
Neighboring chains are connected by intermolecular N-H···N hydrogen bonds between imidazole and triazole groups to form layers parallel to (1 0 0). The N-H···N hydrogen bond is bifurcated with both atoms N4 and N5 acting as acceptor atoms. There are two symmetry-related N-H···N bonds between each pair of molecules. The hydrogen bonded layers are connected along the a axis direction by additional intermolecular weak C-H···O contacts to form a three-dimensional framework.

Experimental
The title compound has been prepared in four steps starting from 4-[(trimethylsilyl)ethynyl]benzaldehyde. The starting material was reacted with benzimidazole in the presence of sodium metabisulfite using microwave irradiation (Navarrete-Vázquez et al., 2007). The resulting product was deprotected with tetrabutylammonium fluoride in tetrahydrofuran to 2-(4-ethynylphenyl)-1H-benzimidazole (Crisp & Flynn, 1993). Cycloaddition of the latter product with [(2-acetoxyethoxy)methyl]azide in the presence of CuI, followed by deprotection of the acetyl group (Krim et al., 2009), afforded the title compound in good yield. The crude product was purified by passing through a column packed with silica gel. Single crystals suitable for X-ray analysis were obtained by slow recrystallizion from ethanol. The melting point is approximately 502-504 K.

Refinement
The H atoms on C atoms were positioned geometrically and treated as riding: C planar -H=0.95 Å, C methylene -H=0.99 Å, U iso (H)=1.2U eq (parent C-atom). The H atoms on the N and O atoms were taken from a difference Fourier synthesis and were refined.

Figure 1
The structure of the title compound, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are drawn as small spheres of an arbitrary radius.

Figure 2
A view of the hydrogen bonding network of the title compound. Displacement ellipsoids are drawn at the 50% probabilty level. Intermolecular hydrogen bonds are shown as dashed lines. The symmetry codes are: (i) 2 -x, 1 -y, 1 -z; (ii) x, 3/2y, 1/2 + z; (v) x, 3/2 -y, -1/2 + z. 1H-1,2,3-triazol-1-yl}methoxy) where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max = 0.001 Δρ max = 0.20 e Å −3 Δρ min = −0.19 e Å −3 Extinction correction: SHELXL97 (Sheldrick, 2008), Fc * =kFc[1+0.001xFc 2 λ 3 /sin(2θ)] -1/4 Extinction coefficient: 0.0056 (7) 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.