Crystal structure of methylene blue citrate
Annotatsiya
Abstract The structure of the salt-type methylene blue citrate hydrate, [MB] + [H 3 Cit] – × 0.18H 2 O (where [MB] + represents the methylene blue cation and [H 3 Cit] – the anion of the mono-deprotonated citric acid), has been determined by single-crystal X-ray diffraction. The [MB] + cation is planar and stacked in an antiparallel fashion, exhibiting π–π stacking associations at an interplane distance of 3.746(6) Å. The [MB] + cation forms short contacts of the C–H⋯O type with the citrate anion through methyl groups of the NMe 2 substituents. Water molecules are distributed in the voids between stacks of the [MB] + cations with very low site occupancies (total 0.18) and do not form hydrogen bonds with the citrate anion, but feature hydrogen bonds between the water molecules. In order to visualize the intermolecular interactions in the crystal structure of the title compound, a Hirshfeld surface analysis was carried out.