反应详情

To a solution of the 4-bromo-3,5-difluoroaniline (5 g, 20 mmol) in acetic acid (60 mL) was added NIS (5.68 g). The reaction mixture was stirred at room temperature for two hours, and poured into water (300 mL). The product was extracted with ethyl acetate (2×200 mL), and the combined organic layers were washed with 1N aqueous NaOH (200 mL) and saturated aqueous sodium thiosulfate (100 mL). The organic layer was dried over sodium sulfate, filtered and concentrated in vacuo. The oily residue was filtered through a plug of silica gel, eluting with heptane/ethyl acetate (4:1). The filtrate was concentrated in vacuo to give the title compound (7.34 g) as a white solid. 1H NMR (500 MHz, CDCl3) δ 6.44 (dd, J=10.00, 1.95 Hz, 1H) 4.46 (br. s., 2H).

1. extractionThe product was extracted with ethyl acetate (2×200 mL)
2. washthe combined organic layers were washed with 1N aqueous NaOH (200 mL) and saturated aqueous sodium thiosulfate (100 mL)
3. dry with materialThe organic layer was dried over sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. filtrationThe oily residue was filtered through a plug of silica gel
7. washeluting with heptane/ethyl acetate (4:1)
8. concentrationThe filtrate was concentrated in vacuo