反应详情

温度

20 °C

To a solution of DMF (18.3 g, 250 mmol) in dichloromethane (300 mL) cooled to 0° C. was added POCl3 (40.5 g, 250 mmol) over a period of 10 minutes. The mixture was stirred at 20° C. for 1 h. To the above mixture was added 282a (28.0 g, 250 mmol) dropwise over a period of 20 minutes. The resulting mixture was heated at reflux for 20 h. The reaction mixture was cooled to room temperature and poured into a solution of sodium acetate (60 g) in ice-water (400 g). The mixture was extracted with dichloromethane (2×300 mL). The combined organic layer was washed with water (2×200 mL), dried over anhydrous Mg2SO4 and filtered. The filtrate was evaporated under reduced pressure to afford 282b as a colorless oil (33.0 g, crude). 1H NMR (500 MHz, DMSO-d6) δ 9.99 (s, 1H), 2.62 (d, J=2.0 Hz, 2H), 2.38 (d, J=2.0 Hz, 2H), 1.15 (s, 6H).

1. temperatureThe resulting mixture was heated
2. temperatureat reflux for 20 h
3. temperatureThe reaction mixture was cooled to room temperature
4. extractionThe mixture was extracted with dichloromethane (2×300 mL)
5. washThe combined organic layer was washed with water (2×200 mL)
6. dry with materialdried over anhydrous Mg2SO4
7. filtrationfiltered
8. customThe filtrate was evaporated under reduced pressure