反应详情

A solution of glacial acetic acid (15 mL), concentrated sulfuric acid (180 mL), and 1-(2-hydroxy-phenyl)-3-(3-methoxy-2-nitrophenyl)propane -1,3 -dione (770 mg, 2.43 mmol) is heated at reflux for 2.5 hours. The hot solution is poured onto crushed ice and H2O (200 mL), stirring vigorously for 30 minutes. The solution is cooled in a refrigerator. The resulting solid is filtered and washed with H2O to yield 2-(3-methoxy-2-nitrophenyl)-4-oxo-4H-[1]benzopyran (510 mg, 70%) as a brown solid.

1. temperatureat reflux for 2.5 hours
2. additionThe hot solution is poured
3. temperatureThe solution is cooled in a refrigerator
4. filtrationThe resulting solid is filtered
5. washwashed with H2O