反应详情

温度

-78 °C

Add dropwise a solution of 1,3-dibromo-5-fluorobenzene (12.39 mL, 98.5 mmol) in tetrahydrofuran (20 mL) to a solution of n-butyllithium (64.61 mL, 103.4 mmol, 1.6 M in hexanes) in tetrahydrofuran (55 mL) at −78° C. Stir at −78° C. for 45 minutes, add dimethylformamide (7.62 mL, 98.5 mmol), stir at −78° C. for 1.5 hours, remove cooling bath and stir 10 minutes. Add saturated aqueous ammonium chloride (150 mL) and extract with diethyl ether (2×700 mL). Wash combined organic layers sequentially with water (1×300 mL) and saturated aqueous sodium chloride (1×300 mL). Dry over magnesium sulfate and concentrate under reduced pressure. Subject residue to silica gel chromatography, eluting with 0-10% ethyl acetate in hexanes to provide the desired compound (11.05 g, 55.3%).

1. stirringstir at −78° C. for 1.5 hours
2. customremove
3. temperaturecooling bath
4. stirringstir 10 minutes
5. extractionAdd saturated aqueous ammonium chloride (150 mL) and extract with diethyl ether (2×700 mL)
6. washWash
7. dry with materialDry over magnesium sulfate
8. concentrationconcentrate under reduced pressure
9. washSubject residue to silica gel chromatography, eluting with 0-10% ethyl acetate in hexanes