反应详情

温度

-78 °C

To a solution of tert-butyl(2,4-difluorophenyl) carbonate (2.3 g, 10 mmol, 1.2 eq.) in THF (50 mL) cooled at −78° C. was added n-BuLi (6.25 mL, 15 mmol, 1.8 eq.) dropwise. The resulting mixture was stirred at −78° C. for 30 min, then a solution of N-methoxy-N-methylquinoxaline-6-carboxamide (1.8 g, 8.7 mmol, 1.0 eq.) in THF (20 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 (50 mL×3). The combined organic layers were dried over anhydrous Na2SO4 and concentrated. The residue was purified via flash column (PE/EA=3/1, v/v) to afford tert-butyl (2,4-difluoro-3-(quinoxaline-6-carbonyl)phenyl) carbonate as yellow foam (1.06 g, 30.3%).

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 (50 mL×3)
4. dry with materialThe combined organic layers were dried over anhydrous Na2SO4
5. concentrationconcentrated
6. customThe residue was purified via flash column (PE/EA=3/1