Date Published: April 01, 2012
Publisher: International Union of Crystallography
Author(s): R. Anitha, S. Athimoolam, S. Asath Bahadur, M. Gunasekaran.
In the title compound, C6H7ClN+·C4H3O4−, the cations and anions lie on mirror planes and hence only half of the molecules are present in the asymmeric unit. The 4-chloroanilinium cation and hydrogen maleate anion in the asymmetric unit are each planar and are oriented at an angle of 15.6 (1)° to one another and perpendicular to the b axis. A characterestic intramolecular O—H⋯O hydrogen bond, forming an S(7) motif, is observed in the maleate anion. In the crystal, the cations and anions are linked by N—H⋯O hydrogen bonds, forming layers in the ab plane. The aromatic rings of the cations are sandwiched between hydrogen-bonded chains and rings formed through the amine group of the cation and maleate anions, leading to alternate hydrophobic (z = 0 or 1) and hydrophilic layers (z = 1/2) along the c axis.
For related structures, see: Anitha et al. (2011 ▶); Balamurugan et al. (2010 ▶); Ploug-Sørenson & Andersen (1985 ▶); Rahmouni et al. (2010 ▶); Smith et al. (2005 ▶, 2007 ▶, 2009 ▶). For the importance of 4-chloroaniline, see: Ashford (2011 ▶); Amoa (2007 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶).