反应详情

To a solution of 39.3 g 5-p-methoxybenzyloxy-2-hydroxymethyl-4-pyrone in 600 ml pyridine, was added 52.2 g hydroxylamine hydrochloride, and the mixture was heated at 70°-75° C. for 2.5 hours. The reaction mixture was concentrated to about 100 ml, 100 ml water was added to the concentrate, and the resulting solution was added under ice cooling to a mixture of 75 ml hydrochloric acid and 225 ml water. After adjusting the pH to 2-2.5, stirring was continued under ice cooling for 30 minutes, and the crystals which separated out were collected by filtration, washed with water and dried, giving 16.6 g of 5-p-methoxybenzyloxy-1-hydroxy-2-hydroxymethyl-4-pyridone.

1. temperaturethe mixture was heated at 70°-75° C. for 2.5 hours
2. concentrationThe reaction mixture was concentrated to about 100 ml, 100 ml water
3. additionwas added to the concentrate
4. additionthe resulting solution was added under ice cooling to a mixture of 75 ml hydrochloric acid and 225 ml water
5. customthe crystals which separated out
6. filtrationwere collected by filtration
7. washwashed with water
8. customdried