反应详情

A mixture of 0.894 gm (3.78 mMol) ethyl 2-oxo-2-(5-fluorobenzofur-7-yl)acetate and 0.143 gm (3.78 mMol) sodium borohydride in 5 mL ethanol was stirred at room temperature for 1 hour. The reaction was quenched by the dropwise addition of water and was then concentrated under reduced pressure. The residue was dissolved in ethyl acetate, washed with water, and the organic phase concentrated under reduced pressure. The residual oil was subjected to flash silica gel chromatography, eluting with chloroform containing 2% methanol. Fractions containing ethyl 2-hydroxy-2-(5-fluorobenzofur-7-yl)acetate were combined and concentrated under reduced pressure. This residue was dissolved in 2.5 mL of pyridine and 2.5 mL acetic anhydride and was stirred at room temperature for 1 hour. The reaction mixture was then diluted with 25 volumes of ethyl acetate, washed with water, and concentrated under reduced pressure to provide 0.675 gm (64%) of the desired compound.

1. customThe reaction was quenched by the dropwise addition of water
2. concentrationwas then concentrated under reduced pressure
3. dissolutionThe residue was dissolved in ethyl acetate
4. washwashed with water
5. concentrationthe organic phase concentrated under reduced pressure
6. washeluting with chloroform containing 2% methanol
7. additionFractions containing ethyl 2-hydroxy-2-(5-fluorobenzofur-7-yl)acetate
8. concentrationconcentrated under reduced pressure
9. dissolutionThis residue was dissolved in 2.5 mL of pyridine
10. stirring2.5 mL acetic anhydride and was stirred at room temperature for 1 hour
11. additionThe reaction mixture was then diluted with 25 volumes of ethyl acetate
12. washwashed with water
13. concentrationconcentrated under reduced pressure