反应详情

A mixture of 20 g of 7-(1-ethoxycarbonylethyl)oxy-3-phenyl-4H-1-benzopyran-4-one, 200 ml of dioxane, 70 ml of hydrochloric acid and 150 ml of water was refluxed for 4 hours and poured into ice water. The resulting crystalline precipitate was collected by filtration and recrystallized from ethanol to give 17.1 g of 7-(1-hydroxycarbonylethyl)oxy-3-phenyl-4H-1-benzopyran-4-one as white crystals. m.p. 223° C.

1. temperaturewas refluxed for 4 hours
2. filtrationThe resulting crystalline precipitate was collected by filtration
3. customrecrystallized from ethanol