2,5-Dihydroxyterephthalic acid dihydrate

Abstract

The title compound, C8H6O6·2H2O, was obtained by accident within a project on the synthesis of metal–organic coordination polymers by the reaction of LiOH with 2,5-dihydroxyterephthalic acid under solvothermal conditions. The asymmetric unit consists of half a 2,5-dihydroxyterephthalic acid molecule located on a centre of inversion and one solvent water molecule that occupies a general position. The 2,5-dihydroxyterephthalic acid molecules are connected to the water molecules via O—H...O hydrogen bonding to form a layer in the ab plane.