反应详情

温度

-78 °C

Methyl magnesium bromide (44 mL, 61.6 mmol, 1.4 M in tetrahydrofuran) was added to tetrahydrofuran (50 mL) at −78° C. (4-Bromo-2-chloro-N-methoxy-N-methyl-benzamide (3.52 g, 12.7 mmol) (from step 6-I) in tetrahydrofuran (30 mL) was added. The mixture was stirred at −78° C. for 45 minutes and then at room temperature for 1.5 hours. The reaction mixture was poured into ice water and saturated aqueous ammonium chloride was added. The mixture was extracted with ethyl acetate (3 times) and the combined organic extracts were washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo. The crude product was recrystallized from ethyl acetate/hexanes to give 1-(4-bromo-2-chloro-phenyl)-ethanone as a white solid (1.1 g, 37%).

1. additionwas added
2. waitat room temperature for 1.5 hours
3. additionwas added
4. extractionThe mixture was extracted with ethyl acetate (3 times)
5. washthe combined organic extracts were washed with brine
6. dry with materialdried over sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe crude product was recrystallized from ethyl acetate/hexanes