反应详情

A solution of 2-(3-(trifluoromethyl)phenyl)-1H-benzo[d]imidazole-4-carboxylic acid (11; 1.53 g, 5.0 mmol), diphenylphosphoryl azide (DPPA, 1.39 g, 5.0 mmol) and Et3N (0.75 g, 7.4 mmol) in toluene (15 mL) was stirred at room temperature for 2 h and then stirred under reflux for 2 h. Benzyl alcohol (0.54 g, 5.0 mmol) was added and the resulting reaction mixture was stirred under reflux for another 12 h. After cooling to room temperature, the mixture was washed successively with aqueous citric acid (10% w/w), saturated NaHCO3 and brine. The organic layer was (Na2SO4), and concentrated under reduced pressure. The resulting residue was purified by chromatography (petroleum ether:ethyl acetate=10:1) to give benzyl 2-(3-(trifluoromethyl)phenyl)-1H-benzo[d]imidazol-4-ylcarbamate 12 (1.45 g, 70%) as a solid. MS (ESI) calcd for C22H16F3N3O2: 411.12; found: 412 [M+H].

1. temperatureunder reflux for 2 h
2. customthe resulting reaction mixture
3. stirringwas stirred
4. temperatureunder reflux for another 12 h
5. washthe mixture was washed successively with aqueous citric acid (10% w/w), saturated NaHCO3 and brine
6. concentrationconcentrated under reduced pressure
7. customThe resulting residue was purified by chromatography (petroleum ether:ethyl acetate=10:1)