反应详情

Add 8.45 mL (50.4 mmol) of triethylsilyl chloride to a suspension of 2.99 g of activated Zn (45.8 mmol) in anhydrous acetonitrile (100 mL) at −20° C. and stir the mixture for 5 minutes. Add 8.0 mL (57.3 mmol) of ethyl 2,2-dibromo-2-fluoracetate and stir the mixture for 90 minutes at −20° C. Add 1.86 mL (22.9 mmol) of 2-cyclopenten-1-one, and stir the reaction mixture overnight, allowing the temperature to rise slowly to room temperature. Add HCl 1N (125 mL) and EtOAc (100 mL). Wash the organic layer with saturated NaHCO3 (2×150 mL), water (2×150 mL) and brine (2×150 mL), dry over anhydrous MgSO4, filter and concentrate under reduced pressure. Purify the residue by column chromatography using EtOAc/hexane (1:8) as eluent to give the title compound (5.36 g, 88% overall yield) as a colorless oil as a mixture of diastereoisomers.

1. stirringstir the mixture for 90 minutes at −20° C
2. stirringstir the reaction mixture overnight
3. customto rise slowly to room temperature
4. washWash the organic layer with saturated NaHCO3 (2×150 mL), water (2×150 mL) and brine (2×150 mL)
5. dry with materialdry over anhydrous MgSO4
6. filtrationfilter
7. concentrationconcentrate under reduced pressure
8. customPurify the residue by column chromatography