反应详情

温度

-68 °C

A solution of diisopropylamine (22.1 mL, 157 mmol) in 140 mL THF was stirred under argon at −68° C. while n-BuLi (57.9 mL, 2.59 M in hexane, 150 mmol) was added in a fine stream in 2 portions over 6 minutes. The resulting pale yellow homogeneous solution was removed from the acetone/dry ice bath and stirred at ambient conditions for 9 minutes, and was then cooled back down to −68° C. and a solution of 1-bromo-4-fluorobenzene (15.6 mL, 143 mmol) in THF (30 mL) was added dropwise over 5 minutes. The reaction was then stirred in the cold bath for another 6 minutes, and the pale yellow reaction was then treated dropwise with a solution of ethyl trifluoroacetate (18.7 mL, 157 mmol) in THF (30 mL) over ˜8 minutes (internal temp rose to −47° C.). The pale yellow reaction was then stirred overnight as the acetone/dry ice bath expired (15 hours). The resulting yellow homogeneous solution was washed with 5 M aqueous NH4Cl (2×50 mL), and the organic layer was dried (Na2SO4), filtered, and concentrated to provide the crude title compound as a clear dark yellow oil.

1. additionwas added in a fine stream in 2 portions over 6 minutes
2. customThe resulting pale yellow homogeneous solution was removed from the acetone/dry ice bath
3. stirringThe reaction was then stirred in the cold bath for another 6 minutes
4. customthe pale yellow reaction
5. customThe pale yellow reaction
6. custom(15 hours)
7. washThe resulting yellow homogeneous solution was washed with 5 M aqueous NH4Cl (2×50 mL)
8. dry with materialthe organic layer was dried (Na2SO4)
9. filtrationfiltered
10. concentrationconcentrated