Ethyl 6-(4-cyclopropyl-1H-1,2,3-triazol-1-yl)pyridine-3-carboxylate

In the title compound, C13H14N4O2, which has approximate mirror symmetry, the dihedral angles between the triazole ring and the cyclopropane and pyridine rings are 87.1 (2) and 7.60 (9)°, respectively. In the crystal, inversion dimers linked by pairs of both C—H⋯N and C—H⋯O interactions generate R 2 2(6) and R 2 2(18) loops, respectively. Further C—H⋯N interactions form R 2 2(10) loops and link the dimers into [110] chains.


Related literature
For background to triazoles, see: Kiselyova et al. (2009) Table 1 Hydrogen-bond geometry (Å , ). MNA is highly thankful to the Higher Education Commission of Pakistan for financial support.

Comment
There are many derivatives of 1-(pyridine-2yl)-1,2,3-triazole that have been used as an intermediates in organic synthesis, or as ligands in coordination chemistry which have shown biologically important properties (Kiselyova et al., 2009;Zhang et al., 2012). As part of our studies in this area, we report here the structure of the title compound (I), (Fig. 1).

Experimental
To a suspension of ethyl tetrazolo [1,5-a]pyridine-6-carboxylate (0.25 g, 1 mmol), copper acetate (0.018 g, 0.1 mmol) in THF (2 ml) was stirred for 10 min, to give a deep red color suspension. Ethynylcyclopropane (0.072 g, 1.1 mmol) was added and the reaction mixture was stirred at room temperature for 40 min. The residue was purified by column chromatography to give 84% of product as white solid. Colourless prisms of (I) were grown by slow evaporation of an ethanol: ethyl acetate solution at room temperature (m.p. 394 K).

Refinement
The H-atoms were positioned geometrically (C-H = 0.93-0.97 Å) and refined as riding with U iso (H) = xU eq (C), where x = 1.5 for methyl and x = 1.2 for other H-atoms.  View of the title compound with displacement ellipsoids drawn at the 50% probability level.

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.