Crystal structure of octane-1,8-diaminium 4,4′-(diazene-1,2-diyl)dibenzoate monohydrate

Abstract

The title salt, C8H22N2 2+·C14H8N2O4 2−·H2O, represents a pseudo-polymer ionic material, resulting from the self-organizing behavior of 4,4′-azinodibenzoate dianions and doubly protonated, 1,8-diaminium-octane cations in aqueous solution. The asymmetric unit consists of two halves of octane 1,8-diaminium cations (the complete cations are both generated by crystallographic inversion symmetry), a 4,4′-azinodibenzoate anion [dihedral angle between the aromatic rings = 10.22 (4)°] and a water molecule of crystallization. One of the cations is in a fully extended linear conformation while the second one has a terminal C—C—C—N gauche conformation. In the crystal, the cations, anions and water molecules are linked into a three-dimensional network via a complex pattern of charge-assisted N—H...O and O—H...O hydrogen bonds.