A ruthenium biimidazole-like anion receptor with two chelating NH⋯O intramolecular hydrogen bonds

•A new ruthenium biimidazole-like anion receptor has been synthesized.•Complex 2·(PF6)2 in CH3CN shows strong affinity towards Cl- and Br-.•The structure of [22·Cl]+ adduct has been determined by X-ray crystallography.

A new ruthenium biimidazole-like anion receptor featuring two “chelating” NH⋯O intramolecular hydrogen bonds, [Ru(bpy)2(DNBbimH2)](PF6)2 (2·(PF6)2) (bpy = 2,2′-bipyridine; DNBbimH2 = 5,5′,6,6′-tetramethyl-7,7′-dinitro-2,2′-bibenzimidazole), has been synthesized. Its anion-binding ability towards different anions in acetonitrile has been studied.

Graphical abstractA new ruthenium biimidazole-like anion receptor featuring two “chelating” NH⋯O intramolecular hydrogen bonds, [Ru(bpy)2(DNBbimH2)](PF6)2 (bpy = 2,2′-bipyridine; DNBbimH2 = 5,5′,6,6′-tetramethyl-7,7′-dinitro-2,2′-bibenzimidazole), has been synthesized. It shows strong affinity towards Cl− and Br−, binds weakly to I−, and shuts out NO3− and HSO4−.Figure optionsDownload full-size imageDownload as PowerPoint slide