Crystal structure of tris­(2-methyl-1H-imidazol-3-ium) benzene-1,3,5-tri­carboxyl­ate

Abstract

The structure of a 2-methyl-1H-imidazol-3-ium-trimesate compound was determined by single-crystal X-ray diffraction. The compound is mixture of protonated and deprotonated mol­ecules.

The structure of the title salt, 3C₄H₇N₂⁺·C₉H₃O₆³⁻ (1), is reported. The compound is formed with three 2-methyl­imidazolium cations and a fully deprotonated trimesic acid. The structure is disordered over two orientations, which were refined using a split model (90.99: 9.01occupancy ratio). Analysis of bond distances and angles reveals the differences and similarities between compound 1 and the previously published 2-methyl-1H-imidazol-3-ium 3,5-di­carb­oxy­benzoate structure [Baletska et al., (2023#). Acta Cryst. E79, 1088–1092] and tris­(2-methyl-1H- imidazol-3-ium) 5-carb­oxy­benzene-1,3-di­carboxyl­ate 3,5-di­carb­oxy­benzoate [Asprilla-Herrera et al. (2025#). Acta Cryst. E81, 303–309], as well as the neutral counterparts of the ions [Tothadi et al. (2020#). ACS Appl. Mater. Inter­faces, 12, 15588–15594; Hachuła et al. (2010#). J. Chem. Crystallogr.40, 201–206]. The crystal packing analysis reveals the formation of hydrogen-bonded two-dimensional networks perpendicular to the [111] vector, where neighbouring planes inter­act via extensive π–π stacking.