2,3-Diamino­pyridinium sorbate–sorbic acid (1/1)

In the title mol­ecular salt–adduct, C₅H₈N₃⁺·C₆H₇O₂⁻·C₆H₈O₂, the 2,3-diamino­pyridinium cation is essentially planar, with a maximum deviation of 0.013 (2) Å, and is protanated at its pyridine N atom. The sorbate anion and sorbic acid mol­ecules exist in extended conformations. In the crystal, the protonated N atom and one of the two amino-group H atoms are hydrogen bonded to the sorbate anion through a pair of N—H...O hydrogen bonds, forming an R₁²(6) ring motif. The carboxyl groups of the sorbic acid mol­ecules and the carboxyl­ate groups of the sorbate anions are connected via O—H...O hydrogen bonds. Furthermore, the ion pairs and neutral mol­ecules are connected via inter­molecular N—H...O hydrogen bonds, forming sheets lying parallel to (100).

Bis(2,3-diamino­pyridinium) phthalate dihydrate

The complete anion of the title hydrated mol­ecular salt, 2C₅H₈N₃⁺·C₈H₄O₄⁻·2H₂O, is generated by a crystallographic twofold axis. In the crystal, the cations, anions and water mol­ecules are connected by N—H...O, O—H...O and C—H...O hydrogen bonds, forming a three-dimensional network. The crystal structure also features C—H...π inter­actions.