C–H···O-Brückenbindungen in Imidazolium-Carboxylaten / C–H···O Hydrogen Bonds in Imidazolium Carboxylates

Abstract

2,3-Dihydro-1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (1) reacts with benzoic acid to give the corresponding 1,3-diisopropyl-4,5-dimethylimidazolium benzoate salt 2. Similarly, 1,3-diisopropyl-4,5-dimethylimidazolium formiate (3) is obtained from 1 and ammonium formiate. In crystals of 2, the anions are linked to the imidazolium ions by monofunctional O···H-C bonds while in 3 bifurcated O・・・H-C bonds are observed. In 1,3-diisopropyl-4,5-dimethylimidazolium hydrogenoxalate (4), obtained from 1 and oxalic acid, hydrogen bonds connect both imidazolium ions to the hydrogenoxalate ions in a bifurcated mode as well as the anions to each other.