反应详情

温度

70 °C

A solution of 6-acetoxy-2-methoxy-2,5,7,8-tetramethylchroman (74.11 g, 266.25 mmol), and concentrated sulfuric acid (2.5 mL) in a mixture of acetone (375 mL) and water 300 mL) was added to a distillation apparatus and warmed at reflux. Distillant was collected until the still head temperature reached 92° C. (about 1.5 h). The slurry was allowed to cool to 70° C. and 240 mL of acetone was added. The resulting mixture was allowed to cool to ambient temperature and the solid that formed was collected filtration. The solid was recrystallized from acetone and dried in a vacuum oven at 60° C. to afford 53.9 g (76.7% yield) of the desired product as a tan solid.

1. additionwas added to a distillation apparatus
2. temperaturewarmed
3. temperatureat reflux
4. distillationDistillant was collected until the still head temperature
5. customreached 92° C.
6. custom(about 1.5 h)
7. addition240 mL of acetone was added
8. temperatureto cool to ambient temperature
9. customthe solid that formed
10. customwas collected
11. filtrationfiltration
12. customThe solid was recrystallized from acetone
13. customdried in a vacuum oven at 60° C.