反应详情

温度

-78 °C

3-(4-(3,4-Dimethoxy-5-nitrophenyl)-3-(ethoxycarbonyl)furan-2-yl)-2-(trifluoro-methyl)pyridine-1-oxide (482 mg, 1 mmol) was taken up in dichloromethane (8 mL). The yellowish suspension was cooled to −78° C. under argon and boron tribromide (0.85 mL, 9 mmol) was added dropwise. The reddish reaction mixture was allowed to warm to room temperature and stirred for 18 hours and then carefully poured into ice-water (100 mL) and stirred for 1 hour. The yellow precipitate was filtered off, washed with water and dried over P2O5 under vacuum. Recrystallisation of the solid from ethanol gave 3-(4-(3,4-Dihydroxy-5-nitrophenyl)-3-(ethoxycarbonyl)furan-2-yl)-2-(trifluoromethyl)pyridine 1-oxide as a yellow solid, 0.31 g (68%).

1. customThe reddish reaction mixture
2. temperatureto warm to room temperature
3. stirringstirred for 1 hour
4. filtrationThe yellow precipitate was filtered off
5. washwashed with water
6. dry with materialdried over P2O5 under vacuum
7. customRecrystallisation of the solid from ethanol