1,4-Bis[2-(2-pyridyl)-1H-imidazol-1-yl]butane

The title compound, C20H20N6, was isolated from dimethyl sulfoxide solution using 2-(1H-imidazol-2-yl)pyridine and 1,4-dichlorobutane in the presence of NaOH.


1,4-Bis[2-(2-pyridyl)-1H-imidazol-1-yl]butane
Ke Tan and Shun-Li Li S1. Comment Numerous flexible or rigid N-heterocyclic precursors have been synthesized and studied because they attract considerable attention because of their diverse coordination capabilities and the important catalytic properties of their metal complexes (Herrmann, 2002;Herrmann & Kocher, 1997). A lot of metal complexes with N-donor ligands, especially ligands with imidazole-type rings separated by an aromatic spacer, have been isolated with various structures (Carlucci et al., 2005).
In the present work, the crystal structure of an N-donor ligand, (I), a newspacer for metal organic frameworks, is reported.
In the molecular structure of the title compound, (I), bond lengths and angles are normal. The dihedral angles between the imidazole ring and the pyridine ring in the same 2-(pyridin-2-yl)-1H-imidazol group are 11.6 and 37.8°, respectively.
The dihedral angle between two imidazole rings in the same ligand is 13.2°. And the corresponding angle between two pyridine rings in the same ligand is 36.4°.

S3. Refinement
All H atoms on C atoms were poisitioned geometrically and refined as idea positions, with C-H = 0.93-0.97 Å, and

Figure 1
A view of the molecule of (I). Displacement ellipsoids are drawn at the 30% probability level.

1,4-Bis[2-(2-pyridyl)-1H-imidazol-1-yl]butane
Crystal data C 20 H 20 N 6 M r = 344.42 Monoclinic, P2 1 /c Hall symbol: -P 2ybc a = 11.0426 (10) Å b = 13.4510 (12) Å c = 12.7081 (11) Å β = 111.213 (2) 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.