反应详情

Zinc (2.439 g, 36.6 mmol) was added to a stirred mixture of 5.01 g (17.8 mmol) of 6-bromo-1,1,2,2-tetrafluoro-1,2-dihydronaphthalene, 11 ml of THF, and 22 ml of NH4OH that was cooled in an ice bath. The mixture was allowed to warm slowly to room temperature. After 4½ hours reaction time, the zinc was removed by filtration. The phases were separated, and the aqueous layer was extracted three times with hexanes. The combined organic phase was washed twice with brine and dried over MgSO4. The MgSO4 was filtered off, and the solvent removed under vacuum. Crude 6-bromo-1,2-difluoronaphthalene (4 g) containing 15% impurities (estimated) remained. The estimated yield of the crude 6-bromo-1,2-difluoronaphthalene was 91%. Brown needles (2.0 g, 8.3 mmol, 46% yield) were recovered after recrystallization from hexanes.

1. temperaturewas cooled in an ice bath
2. customAfter 4½ hours reaction time
3. customthe zinc was removed by filtration
4. customThe phases were separated
5. extractionthe aqueous layer was extracted three times with hexanes
6. washThe combined organic phase was washed twice with brine
7. dry with materialdried over MgSO4
8. filtrationThe MgSO4 was filtered off
9. customthe solvent removed under vacuum
10. additionCrude 6-bromo-1,2-difluoronaphthalene (4 g) containing 15% impurities (estimated)