反应详情

4-(2,4-Bis-benzyloxy-5-isopropyl-phenyl)-2-hydroxy-4-oxo-but-2-enoic acid ethyl ester (1 eq) was dissolved in ethanol with stirring. Hydroxylamine hydrochloride (1.2 eq) was added and the solution was heated to reflux for 4 hours under a nitrogen atmosphere. The reaction mixture was cooled to room temperature and concentrated in vacuo. The residue was partitioned between brine and dichloromethane. The organic phase was dried over MgSO4, filtered and concentrated in vacuo to give 5-(2,4-Bis-benzyloxy-5-isopropyl-phenyl)-isoxazole-3-carboxylic acid ethyl ester as a solid.

1. temperaturethe solution was heated
2. temperatureto reflux for 4 hours under a nitrogen atmosphere
3. concentrationconcentrated in vacuo
4. customThe residue was partitioned between brine and dichloromethane
5. dry with materialThe organic phase was dried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo