反应详情

4-hydroxy -2-methylbenzimidazole (0.57 g, 3.8 mmol) was dissolved in acetonitrile (4 ml). To the solution were added sodium hydroxide (0.17 g, 43 mmol) (dissolved in 1 ml water) and 2,6-dimethyl-4-fluorobenzylbromide (0.82 g, 3.8 mmol) dissolved in acetonitrile (6 ml) and the reaction mixture was refluxed for 80 min. and was stirred for 20 h. at ambient temperature. To the reaction mixture was added methylene chloride (25 ml) and water (25 ml). The organic layer was separated, washed three times with 2 M NaOH, dried over sodium sulfate and was evaporated under reduced pressure. The residue was crystallized from ethyl acetate and was then purified twice by column chromatography on silica gel a) methylene chloride: methanol (10:1) b) ethyl acetate: methanol:acetic acid: water (96:6:6:4). There was obtained 0.066 g (6%) of the title compound.

1. temperaturethe reaction mixture was refluxed for 80 min.
2. customThe organic layer was separated
3. washwashed three times with 2 M NaOH
4. dry with materialdried over sodium sulfate
5. customwas evaporated under reduced pressure
6. customThe residue was crystallized from ethyl acetate
7. customwas then purified twice by column chromatography on silica gel a) methylene chloride: methanol (10:1) b) ethyl acetate: methanol:acetic acid: water (96:6:6:4)