反应详情

A mixture of ethyl 2-(4-oxo-4H-pyran-3-yloxy)acetate (198 g) in 10% hydrochloric acid (10 ml) was heated at 70° to 75° C. for an hour under stirring. The reaction mixture was cooled and concentrated to the volume of about 5 ml. Precipitated crystals were collected by filtration washed with water and dried to give crystals (1.8 g) of 2-(4-oxo-4H-pyran-3-yloxy)acetic acid monohydrate, mp 155° to 157° C.

1. temperaturewas heated at 70° to 75° C. for an hour
2. temperatureThe reaction mixture was cooled
3. concentrationconcentrated to the volume of about 5 ml
4. customPrecipitated crystals
5. filtrationwere collected by filtration
6. washwashed with water
7. customdried