反应详情

Dry hydrogen chloride was passed through a solution of 4-hydroxy-7-methylcoumarin (14 g; 0.08 mole) in ethanol (300 ml) for 15 mins and the resulting solution was refluxed for 30 minutes. After cooling, the solvent was removed in vacuo and the residue recrystallized from ethanol to give 11.74 g (72%) of product of m.p. 142°-143° C.; (Found; C, 70.24; H, 5.95; C12H12O3 requires; C, 70.60; H, 5.88%).

1. temperaturethe resulting solution was refluxed for 30 minutes
2. temperatureAfter cooling
3. customthe solvent was removed in vacuo
4. customthe residue recrystallized from ethanol