Received 9 November 2011
In the crystal structure of the title compound, C20H44NO2+·Br-, the cation and anion are connected via an O-HBr hydrogen bond, forming an ionic pair. The cation is disordered over two conformations related by a mirror plane, and the anion is situated on a mirror plane so that the asymmetric unit contains half of the ionic pair. The long alkyl chain in the cation adopts an all-trans conformation. The crystal packing exhibits weak intermolecular C-HO interactions.
Data collection: SMART (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: 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: CV5198 ).
We acknowledge the National Natural Science Foundation of China (grant No. 21073081) for financial support.
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