5-Chloro-1H-indole-3-carb­oxy­lic acid

Han, X.-L.; Luo, Y.-H.

doi:10.1107/S1600536811053384

Volume 68
Part 1
Page o145
January 2012

Received 5 December 2011
Accepted 12 December 2011
Online 17 December 2011

Key indicators
Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.002 Å
R = 0.037
wR = 0.104
Data-to-parameter ratio = 15.6
Details

5-Chloro-1H-indole-3-carboxylic acid

Xue-Lian Han ^a ^* and Yang-Hui Luo ^a

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

In the title compound, C₉H₆ClNO₂, the carboxyl group is twisted from the indole ring system by 9.00 (8)°. In the crystal, inversion dimers linked by pairs of O-HO hydrogen bonds generate R₂²(8) loops and N-HO hydrogen bonds link the dimers into (001) sheets. Aromatic [pi] - [pi] stacking interactions [centroid-centroid distance = 3.7185 (12) A °] are also observed.

Related literature

For background to indole derivatives as pharmaceuticals, see: Kunzer & Wendt (2011); Woodward & Bartel (2005).

Experimental

Crystal data

C₉H₆ClNO₂
M_r = 195.60
Orthorhombic, P b c a
a = 7.2934 (15) Å
b = 13.065 (3) Å
c = 17.902 (4) Å
V = 1705.9 (6) Å³
Z = 8
Mo K radiation
= 0.41 mm^-1
T = 293 K
0.30 × 0.20 × 0.15 mm

Data collection

Rigaku SCXmini CCD diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005) T_min = 0.907, T_max = 0.941
16050 measured reflections
1919 independent reflections
1590 reflections with I > 2(I)
R_int = 0.050

Refinement

R[F² > 2(F²)] = 0.037
wR(F²) = 0.104
S = 1.04
1919 reflections
123 parameters
H atoms treated by a mixture of independent and constrained refinement
_max = 0.17 e Å^-3
_min = -0.23 e Å^-3

Table 1
Hydrogen-bond geometry (Å, °)

D-HA	D-H	HA	DA	D-HA
O1-H1O2ⁱ	0.82	1.86	2.6558 (17)	164
N1-H1BO2ⁱⁱ	0.86 (2)	2.26 (2)	3.005 (2)	144.3 (19)
Symmetry codes: (i) -x, -y+2, -z+1; (ii) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z]$ .

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: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: SHELXL97.

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB6559 ).

Acknowledgements

We thank Southeast University for support.

References

Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.
Kunzer, A. R. & Wendt, M. D. (2011). Tetrahedron, 52, 1815-1818.
Rigaku. (2005). CrystalClear. Rigaku Corporation, Tokyo, Japan.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.
Woodward, A. W. & Bartel, B. (2005). Ann. Bot. (London), 95, 707-735.

organic compounds