organic compounds
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The asymmetric unit of the title compound, 2C13H14N2O3·C3H10NO3+·Cl−, contains two independent molecules (A and B) of the title pyrimidine derivative and one ion-pair of tris(hydroxymethyl)ammonium chloride. The pyrimidine ring in each pyrimidine derivative has a half-chair conformation. Its mean plane is inclined to the benzene ring by 87.2 (3)° in molecule A and 85.7 (2)° in molecule B. In the crystal, the pyrimidine derivatives are connected to each other by N—HO hydrogen bonds, forming chains propagating along the b-axis direction. The chains are linked via O—H—Cl hydrogen bonds, forming corrugated sheets lying parallel to the bc plane. The sheets are linked via C—HO hydrogen bonds, forming a three-dimensional framework. The tris(hydroxymethyl)ammonium chloride molecules are located in the cages of the framework. There are also further C—HO hydrogen bonds and C—Hπ interactions present in the three-dimensional framework structure. Both the cation and chloride anion of the tris(hydroxymethyl)ammonium chloride ion pair are disordered over two positions, with a refined occupancy ratio of 0.418 (8):0.582 (8) for the cation and 0.71 (4):0.29 (4) for the anion.