Oxalic acid–pyridine-4-carbonitrile (1/2)

Zheng, W.-N.

doi:10.1107/S1600536812019137

Volume 68
Part 6
Page o1625
June 2012

Received 19 April 2012
Accepted 28 April 2012
Online 5 May 2012

Key indicators
Single-crystal X-ray study
T = 298 K
Mean (C-C) = 0.002 Å
R = 0.036
wR = 0.101
Data-to-parameter ratio = 14.8
Details

Oxalic acid-pyridine-4-carbonitrile (1/2)

Wen-Ni Zheng ^a ^*

^aCollege of Chemistry and Chemical Engineering, Southeast University, Nanjing 210096, People's Republic of China
Correspondence e-mail: chenxinyuanseu@yahoo.com.cn

In the title compound, 2C₆H₄N₂·C₂H₂O₄, the oxalic acid molecule lies about an inversion center. The pyridine ring of the pyridine-4-carbonitrile molecule is almost planar, the largest deviation from the least-squares plane being 0.006 (1) Å; the nitrile N atom deviates from this plane by 0.114 (1) Å. In the crystal, the oxalic acid molecules and the pyridine-4-carbonitrile molecules form stacks. Neighboring molecules within the stacks are related by translation in the a direction, with interplanar distances of 3.183 (1) and 3.331 (2) Å, respectively. Each oxalic acid molecule forms strong O-HN hydrogen bonds with two molecules of pyridine-4-carbonitrile. Besides this, there are also weak C-HO interactions.

Related literature

For the structures and ferroelectric properties of related compounds, see: Fu et al. (2011a,b,c); Dai & Chen (2011); Xu et al. (2011); Zheng (2011). For standard bond lengths, see: Allen et al. (1987).

Experimental

Crystal data

C₆H₄N₂·0.5C₂H₂O₄
M_r = 149.13
Triclinic, $[P \overline 1]$
a = 3.6842 (6) Å
b = 7.5816 (5) Å
c = 12.4511 (1) Å
= 78.258 (1)°
= 85.301 (1)°
= 82.547 (1)°
V = 337.08 (6) Å³
Z = 2
Mo K radiation
= 0.11 mm^-1
T = 298 K
0.10 × 0.03 × 0.03 mm

Data collection

Rigaku SCXmini Mercury2 diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005) T_min = 0.910, T_max = 1.000
3634 measured reflections
1528 independent reflections
1268 reflections with I > 2(I)
R_int = 0.024

Refinement

R[F² > 2(F²)] = 0.036
wR(F²) = 0.101
S = 1.04
1528 reflections
103 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
_max = 0.46 e Å^-3
_min = -0.27 e Å^-3

Table 1
Hydrogen-bond geometry (Å, °)

D-HA	D-H	HA	DA	D-HA
O1-H1N1	0.82 (1)	1.80 (1)	2.6173 (12)	176 (2)
C4-H4AO1ⁱ	0.93	2.48	3.3640 (13)	160
Symmetry code: (i) x, y+1, z.

Data collection: CrystalClear (Rigaku, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; 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: SHELXTL.

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: YK2054 ).

Acknowledgements

This work was supported by a start-up grant from Southeast University, China.

References

Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.
Dai, J. & Chen, X.-Y. (2011). Acta Cryst. E67, o287.
Fu, D.-W., Zhang, W., Cai, H.-L., Ge, J.-Z., Zhang, Y. & Xiong, R.-G. (2011c). Adv. Mater. 23, 5658-5662.
Fu, D.-W., Zhang, W., Cai, H.-L., Zhang, Y., Ge, J.-Z., Xiong, R.-G. & Huang, S. P. D. (2011a). J. Am. Chem. Soc. 133, 12780-12786.
Fu, D.-W., Zhang, W., Cai, H.-L., Zhang, Y., Ge, J.-Z., Xiong, R.-G., Huang, S. P. D. & Nakamura, T. (2011b). Angew. Chem. Int. Ed. 50, 11947-11951.
Rigaku (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.
Xu, R.-J., Fu, D.-W., Dai, J., Zhang, Y., Ge, J.-Z. & Ye, H.-Y. (2011). Inorg. Chem. Commun. 14, 1093-1096.
Zheng, W.-N. (2011). Acta Cryst. E67, m344.

organic compounds