反应详情

5.0 g of 4-hydroxy-5-methoxy-isophthalaldehyde are treated with 50 ml of constant-boiling hydrobromic acid and heated to boiling under reflux and while stirring under an argon atmosphere for 3 hours. After cooling 50 ml of ice-water are added thereto, and the separated precipitate is filtered under suction and washed with water. The crude product is taken up in ethyl acetate and filtered over 50 g of aluminum oxide (activity grade II). The crystalline material obtained is recrystallized from ethyl acetate/n-hexane. There is obtained 4,5-dihydroxyisophthalaldehyde in the form of slightly orange crystals of m.p. 201°-202°.

1. temperatureheated
2. temperatureunder reflux
3. additionare added
4. filtrationthe separated precipitate is filtered under suction
5. washwashed with water
6. filtrationfiltered over 50 g of aluminum oxide (activity grade II)
7. customThe crystalline material obtained
8. customis recrystallized from ethyl acetate/n-hexane