Ethyl 1-(2,6-difluoro­benz­yl)-1H-1,2,3-triazole-4-carboxyl­ate

Jing Jia; Dingqiang Lu

doi:10.1107/S1600536810050014

. 2010 Dec 15;67(Pt 1):o127. doi: 10.1107/S1600536810050014

Ethyl 1-(2,6-difluorobenzyl)-1H-1,2,3-triazole-4-carboxylate

Jing Jia ^a, Dingqiang Lu ^a,^*

PMCID: PMC3050293 PMID: 21522638

Abstract

In the title compound, C₁₂H₁₁F₂N₃O₂, the dihedral angle between the triazole and phenyl rings is 73.74 (9)°. In the crystal, molecules are linked into chains along [010] via weak C—H⋯O and C—H⋯N hydrogen bonds.

Related literature

The title compound is an intermediate in the synthesis of rufinamide, a new anti-epilepsy drug (Herranz, 2008 ▶). For synthetic procedures, see: Abu-Orabi et al. (1989 ▶); Wang & Xie (2004 ▶). For a related structure, see: Xiao et al. (2008 ▶).

Experimental

Crystal data

C₁₂H₁₁F₂N₃O₂
M _r = 267.24
Monoclinic,
a = 9.4540 (19) Å
b = 10.963 (2) Å
c = 12.167 (2) Å
β = 93.21 (3)°
V = 1259.1 (4) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 293 K
0.30 × 0.20 × 0.20 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.965, T _max = 0.977
3270 measured reflections
2316 independent reflections
1629 reflections with I > 2σ(I)
R _int = 0.026
3 standard reflections every 200 reflections intensity decay: 1%

Refinement

R[F ² > 2σ(F ²)] = 0.055
wR(F ²) = 0.163
S = 1.03
2316 reflections
174 parameters
H-atom parameters constrained
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994 ▶); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810050014/pv2364sup1.cif

e-67-0o127-sup1.cif^{(17.6KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810050014/pv2364Isup2.hkl

e-67-0o127-Isup2.hkl^{(113.8KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7B⋯O1ⁱ	0.97	2.47	3.415 (3)	166
C8—H8⋯N3ⁱ	0.93	2.61	3.536 (3)	172

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Symmetry code: (i) Inline graphic .

Acknowledgments

The authors thank the Center of Testing and Analysis, Nanjing University, for support.

supplementary crystallographic information

Comment

Epilepsia has been a common disease for a long time and has been on an increase year after year. Rufinamide is a new drug to cure epilepsia; it is a triazole derivative (Herranz et al., 2008). We report herein the crystal structure of the title compound which is a key intermediate in the synthesis of rufinamide. In the title compound (Fig. 1), the planes of the triazole and phenyl rings are not coplanar [dihedral angle 73.74 (9)°]. The discrete molecules are linked through weak C—H···O and C—H···N hydrogen bonds, forming one-dimensional chains along [010] direction (Fig. 2 and Tab. 1). In the structure of the title compound, the bond lengths and angles agree with the corresponding values reported for a related compound (Xiao et al., 2008).

Experimental

The title compound, was prepared by following procedures reported earlier (Wang et al., 2004; Abu-Orabi et al., 1989). To a solution of 2-(azidomethyl)-1,3-difluorobenzene (1.69 g, 10 mmol) in etanol (50 mL), ethyl propiolate (0.98 g, 10 mmol) was added and the mixture was heated under reflux for 10 h. After removing the solvent under reduced pressure the residue was dissolved and the title compound recrystallized from petroleum ether-methanol mixture (15:2), to provide crystals suitable for X-ray diffraction (yield 2.31 g, 86.3%).