1,2-Bis(pyridin-4-yl)diazene–3,4,5-trihydroxybenzoic acid–methanol (3/2/2)

Abstract

The title compound, 3C10H8N4·2C7H6O5·2CH4O, has a molecular crystal structure which results from the cocrystallization of gallic acid (GA), 4,4′-azodipyridine (AzPy) and methanol in a 2:3:2 molar ratio. The asymmetric unit comprises one molecule each of GA, AzPy and methanol in general positions and half a molecule of AzPy as this is located about a centre of inversion. In the crystal, all the components of the structure are associated via the extended system of hydrogen bonds (O—H...O and O—H...N) and π–π stacking interactions [centroid–centroid distance = 3.637 (3) Å] into two-dimensional supramolecular layers which are packed parallel to the [101] plane. The shortest perpendicular distance and the slippage between aromatic groups are 3.395 (3) and 2.152 (3) Å, respectively. The AzPy molecules display a trans conformation with respect to the azo groups.