Imidazolium Phenolates

1,3-Diisopropyl-4,5-dimethylimidazolium phenolate (4a), pentafluorophenolate (4b), and pentachlorophenolate (4c) are obtained from 2,3-dihydro- 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (2) and the corresponding phenols 3 as stable crystals in excellent yields, The crystal structure analyses of compounds 4 reveal the presence of ion pairs linked by almost linear C-H center dot center dot center dot O hydrogen bonds. With 4-hydroxypyridine (5), the carbene 2 gives 1,3-diisopropyl-4,5-dimethylimidazolium 4-pyridinolate (6) whose crystal structure analysis indicates the ions to be connected by a C-H center dot center dot center dot N bond.