Date Published: May 01, 2012
Publisher: International Union of Crystallography
Author(s): Christian Neis, Günter J. Merten, Philipp Altenhofer, Kaspar Hegetschweiler.
The crystal structure of the title compound, C6H16N2O32+·2Cl−, has been reported previously by Palm [Acta Cryst. (1967 ▶), 22, 209–216] from Weisenberg camera data, with R1 = 10.5%, isotropic refinement of non-H atoms and H atoms not located. We remeasured a data set of the title compound and present a more precise structure determination. The asymmetric unit contains two unique 1,3-diammonio-1,2,3-trideoxy-cis-inositol cations and four Cl− counter-ions. The cyclohexane rings of both inositol cations adopt chair conformations with two axial hydroxy groups. An extended network of hydrogen bonds is formed. The four chloride counter ions are hydrogen bonded to the hydroxy and ammonium groups of the cations by N—H⋯Cl and O—H⋯Cl interactions. The cations are aligned into wavy layers by cation⋯cation interactions of the form N—H⋯O(ax), N—H⋯O(eq) and O(ax)—H⋯O(eq). Intramolecular hydrogen bonding between the axial hydroxy groups is, however, not observed.
An earlier, less accurate structure determination of the title compound was performed by Palm (1967 ▶). The crystal structure of 1,3-diammonio-1,2,3-trideoxy-cis-inositol sulfate has been reported by Neis et al. (2012 ▶). The importance of intramolecular hydrogen bonding in 1,3,5-trisubstituted cyclohexane derivatives has been described by Gencheva et al. (2000 ▶), Saaidi et al. (2008 ▶) and Neis et al. (2010 ▶), and the implication of increased 1,3-diaxial repulsion on the conformation of a cyclohexane ring has been discussed by Fritsche-Lang et al. (1985 ▶), Kramer et al. (1998 ▶) and Kuppert et al. (2006 ▶). For the synthesis, see: Merten et al. (2012 ▶). For the treatment of hydrogen atoms in SHELXL, see: Müller et al. (2006 ▶).