反应详情

温度

-78 °C

To a solution of tert-butyl (2,4,5-trifluorophenyl)carbamate (2.72 g, 11 mmol, 1.1 eq.) in THF (150 mL) cooled at −78° C. was added n-BuLi (9.17 mL, 22 mmol, 2.2 eq.) dropwise. The resulting mixture was stirred at −78° C. for 30 min, then a solution of N-methoxy-N-methylquinoxaline-6-carboxamide (2.17 g, 10 mmol, 1.0 eq.) in THF (50 mL) was added dropwise. The resulting mixture was stirred at −78° C. for 1 h, then quenched by the addition of NH4Cl solution. The mixture was extracted with EA (100 mL×3). The combined organic layers were dried over Na2SO4 and concentrated. The resulting residue was purified by flash column chromatography (PE/EA=4/1, v/v) to afford tert-butyl (2,4,5-trifluoro-3-(quinoxaline-6-carbonyl)phenyl)carbamate as yellow foam (600 mg, 14.9%)

1. stirringThe resulting mixture was stirred at −78° C. for 1 h
2. customquenched by the addition of NH4Cl solution
3. extractionThe mixture was extracted with EA (100 mL×3)
4. dry with materialThe combined organic layers were dried over Na2SO4
5. concentrationconcentrated
6. customThe resulting residue was purified by flash column chromatography (PE/EA=4/1