反应详情

温度

0 °C

To a 2 L rounded bottom flask equipped with a condenser and a mechanical stirrer was placed 1A (250.7 g, 0.8851 mol), dioxane (300 mL) and concentrated HCl (60 mL). The reaction mixture was heated to reflux and stirred under N2 for 20 hours. Water (250 mL) was added dropwise while maintaining the reaction mixture at reflux. After cooling to 0° C. with an ice/water bath, the resulting slurry was stirred for 30 minutes and then filtered. The cake was washed with water (4×200 mL) and suction dried for 17 hours to give 1B (146.3 g, 91%) as yellow solid. 1H NMR (CDCl3) d 10.54 (s, 1H), 8.00 (d, J=8.3 Hz, 1H), 7.91 (s, 1H), 7.89 (d, J=8.3 Hz, 1H), 4.08(s, 3H).

1. customTo a 2 L rounded bottom flask equipped with a condenser and a mechanical stirrer
2. temperatureThe reaction mixture was heated
3. temperatureto reflux
4. temperaturewhile maintaining the reaction mixture
5. temperatureat reflux
6. stirringthe resulting slurry was stirred for 30 minutes
7. filtrationfiltered
8. washThe cake was washed with water (4×200 mL) and suction
9. customdried for 17 hours