Tetra-kis(2,6-diamino-pyridinium) diphthalate 2,6-diamino-pyridine

Abstract

In the title compound, 4C(5)H(8)N(3) (+)·2C(8)H(4)O(4) (2-)·C(5)H(7)N(3), the asymmetric unit consists of two protonated diamino-pyridine cations, one phthalate anion and one half of a diamino-pyridine mol-ecule, which has twofold rotation symmetry and is disordered over two positions with a site-occupancy ratio of 0.534 (3):0.466 (3). In the disordered structure, both pyridine rings are essentially planar, with maximum deviations of 0.011 (2) and 0.006 (2) Å, and these two rings are inclined to one another at a dihedral angle of 79.86 (10)°. In the crystal structure, inter-molecular N-H⋯O and C-H⋯O hydrogen bonds link the ions and mol-ecules into a three-dimensional network. The structure is further stabilized by C-H⋯π inter-actions.

Fig. 1.

The molecular structure of the title compound, showing 30% probability displacement ellipsoids and the atom-numbering scheme. Open bonds indicate the minor disordered component.

Fig. 2.

The crystal packing of the title compound, viewed along the c axis, showing the three-dimensional network. Only major components are shown. H atoms not involved in intermolecular interactions (dashed lines) have been omitted for clarity.