反应详情

温度

60 °C

To a stirred solution of 2-fluoro-4,5-dihydroxy-benzaldehyde (8.0 g) and BrClCH2 (24.8 g, 190 mmol) in dry DMF (50 mL) was added Cs2CO3 (62.0 g, 190 mmol) in portions. The resulting mixture was stirred at 60° C. overnight and then poured into water. The mixture was extracted with EtOAc (200 mL×3). The combined organic layers were washed with brine (200 mL), dried over Na2SO4, and evaporated in vacuo to give crude product, which was purified by column chromatography on silica gel (5-20% ethyl acetate/petroleum ether) to afford 6-fluoro-benzo[1,3]dioxole-5-carbaldehyde (700 mg, two steps yield: 24%). 1H-NMR (400 MHz, CDCl3) δ 10.19 (s, 1H), 7.23 (d, J=5.6, 1H), 6.63 (d, 9.6, 1H), 6.08 (s, 2H).

1. extractionThe mixture was extracted with EtOAc (200 mL×3)
2. washThe combined organic layers were washed with brine (200 mL)
3. dry with materialdried over Na2SO4
4. customevaporated in vacuo
5. customto give crude product, which
6. customwas purified by column chromatography on silica gel (5-20% ethyl acetate/petroleum ether)