Date Published: June 01, 2010
Publisher: International Union of Crystallography
Author(s): Madhukar Hemamalini, Hoong-Kun Fun.
The title salt, C5H6ClN2+·C3H3O4−, contains two cations and two anions in the asymmetric unit. Both 2-amino-5-chloropyridinium ions are protonated at their pyridine N atoms and both hydrogen malonate ions feature an intramolecular O—H⋯O hydrogen bond, which generates an S(6) ring motif and results in a folded conformation. In the crystal structure, the cations and anions are linked via N—H⋯O, O—H⋯O and C—H⋯O hydrogen bonds, forming chains propagating in , which are cross-linked by further C—H⋯O interactions.
For background to the chemistry of substituted pyridines, see: Amr et al. (2006 ▶); Bart et al. (2001 ▶); Shinkai et al. (2000 ▶); Klimesôva et al. (1999 ▶). For related structures, see: Pourayoubi et al. (2007 ▶); Janczak & Perpétuo (2009 ▶); Akriche & Rzaigui (2005 ▶). For details of hydrogen bonding, see: Jeffrey & Saenger (1991 ▶); Jeffrey (1997 ▶); Scheiner (1997 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For bond-length data, see: Allen et al. (1987 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).