Piperazine-1,4-diium bis(2,4,5-tricarboxybenzoate) dihydrate

Abstract

In the title hydrated salt, C4H12N22+·2C10H5O8−·2H2O, the piperazinediium cation, lying about an inversion center, adopts a chair conformation. The benzene ring of the anion makes dihedral angles of 25.17 (8)° with the carboxylate group and angles of 8.50 (7), 20.07 (7) and 80.86 (8)° with the three carboxylic acid groups. In the crystal, the cations, anions and water molecules are connected by O—H...O and N—H...O hydrogen bonds into double layers parallel to (110).