反应详情

温度

-78 °C

A 1.0 M boron tribromide solution in dichloromethane (24 mL, 24 mmol, 2.4 equiv) was added dropwise over 30 minutes, at −78° C., to a solution of compound 2 (3.0 g, 10.2 mmol, 1 equiv) in dichloromethane (100 mL). The reaction was stirred at −78° C. for 3 hours, when 1H NMR indicated that the reaction was complete. The reaction was poured into saturated sodium bicarbonate (200 mL) and the pH was adjusted to 8 with 10% sodium hydroxide. The layers were separated, then the aqueous phase was extracted with dichloromethane (2×100 mL). The combined organic layers were dried over sodium sulfate, filtered, and concentrated under reduced pressure. The residue was purified over silica gel (40 g), eluting with a gradient of 0 to 20% ethyl acetate in heptanes to give 2′,3′,4′,5,5′,6′-hexafluoro-[1,1′-biphenyl]-2-ol (3) (2.3 g, 80% yield) as a white solid.

1. customThe layers were separated
2. extractionthe aqueous phase was extracted with dichloromethane (2×100 mL)
3. dry with materialThe combined organic layers were dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated under reduced pressure
6. customThe residue was purified over silica gel (40 g)
7. washeluting with a gradient of 0 to 20% ethyl acetate in heptanes