反应详情

5,6-Dimethyl-4-hydroxy-2-oxo-2H-pyran (11.92 g) (see J.C.P.Perkin Trans. 1, 1980, 2272) was dissolved in 1,4-dioxane (80 ml), aqueous 35% ammonia solution (40 ml) was added and the mixture was heated under reflux for 90 minutes. The solution was left to cool overnight, the precipitate filtered off and dried under reduced pressure at 90° C. for 24 hours to yield 2,4-dihydroxy-5,6-dimethylpyridine (3.47 g) as a white solid.

1. temperaturethe mixture was heated
2. temperatureunder reflux for 90 minutes
3. waitThe solution was left
4. temperatureto cool overnight
5. filtrationthe precipitate filtered off
6. customdried under reduced pressure at 90° C. for 24 hours