Bis(2-hydroxyethanaminium) terephthalate

The asymmetric unit of the title salt, 2C2H8NO+·C8H4O4 2−, comprises one crystallographically independent 2-hydroxyethanaminium cation and one half terephthalate anion. In the crystal, hydrogen bonds involving the hydroxy and ammonium groups of the cations and the carboxylate O atoms of the terephthalate anions result in the formation of a three-dimensional network structure.

The asymmetric unit of the title salt, 2C 2 H 8 NO + ÁC 8 H 4 O 4 2À , comprises one crystallographically independent 2-hydroxyethanaminium cation and one half terephthalate anion. In the crystal, hydrogen bonds involving the hydroxy and ammonium groups of the cations and the carboxylate O atoms of the terephthalate anions result in the formation of a threedimensional network structure.
The author thanks the Ordered Matter Science Research Center, Southeast University for its excellent experimental conditions and its generous financial support.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BX2389).  (Zhang et al., 2005;Smith & Wermuth, 2010;Karpova et al., 2004) as well as their physical properties (Zhang et al., 2010;Zhang et al., 2008;Wu et al., 2011). We report here the crystal structure of the title compound, Fig.1. The asymmetric unit of the title salt, 2(C 2 H 8 NO) + .

Structure Reports Online
(C 8 H 4 O 4 ) 2comprises one crystallographically independent 2-hydroxyethanaminium cation and one-half-terephthalate anion. In the crystal structure, hydrogen bonds involving the hydroxy and ammonium groups connect the carboxyl O atoms of the terephthalate anion into a three-dimensional network structure, Figure 2, Table1.

Experimental
The title compound was synthetized from a mixture of NH 2 (CH 2 ) 2 OH (122.16 mg, 2.00 mmol), C 8 H 6 O 4 (166.13 mg, 1.00 mmol), and distilled water (10 mL), which was stirred a few minutes at room temperature, giving a clear transparent solution.
After evaporation for a few days, block colorless crystals suitable for X-ray diffraction were obtained in about 77% yield, which were filtered and washed with distilled water.   showing the hydrogen bonds interactions. Symmetry code: (i) x-1/2, -y+1/2, z+1/2; (ii) -x+3/2, y-1/2, -z+1/2; (iii) x-1, y, z; (iv) -x+1, -y, -z. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating Rfactors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.