Received 13 August 2008
The two aromatic rings of each of the four independent molecules in the asymmetric unit of the title compound, C11H9ClN2, are approximately coplanar; the four molecules are arranged into two amino-pyridyl N-HN hydrogen-bonded pairs. The structure has a 15% twin component related by a twofold rotation about .
Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: PK2115 ).
We thank Dr Sean Parkin of the University of Kentucky for discussion of the twinning problem, and we thank the University of Malaya for supporting this study (grant No. FS358/2008 A).
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