Bis(2,6-diaminopyridinium) hydrogen phthalate nitrate monohydrate

Abstract

The title hydrated salt, 2C5H8N3+·C8H5O4-·NO3-·H2O, was obtained fortuitously from the reaction between 2,6-diamino-pyridine, phthalic acid and Co(NO3)2·6H2O at 343 K. The asymmetric unit consists of two crystallographically independent 2,6-diamino-pyridinium cations, a hydrogen phthalate anion, a nitrate ion and a water mol-ecule of crystallization which in the crystal structure are linked by inter-molecular O - H⋯O and N - H⋯O hydrogen bonds into a three-dimensional network. In the hydrogen phthalate anion, there is a very strong intra-molecular O - H⋯O hydrogen bond.