反应详情

A mixture of 24.5 g of methyl 4,5bis(4-methoxyphenyl)-5-oxo-3-pentenoate and 51.5 g of hydroxylamine hydrochloride in a mixture of 650 ml of methanol and 72 ml of water was heated under reflux for 3 hours. During this procedure, 0.9 equivalent of sodium hydrogen carbonate was added portionwise to the reaction mixture as the reaction progressed. After completion of the reaction, the methanol was distilled off under reduced pressure. Water and ethyl acetate were added to the residue for dissolution thereof, the organic layer was separated, washed with saturated aqueous sodium chloride solution and dried over anhydrous magnesium sulfate. The organic layer was then concentrated under reduced pressure and the residue was separated and purified by silica gel column chromatography (developing solvent: ethyl acetate:n-hexane=1:4) to give 23 g (yield 90%) of methyl 5-hydroxyimino-4,5-bis(4-methoxyphenyl)-3-pentenoate as an oil.

1. temperaturewas heated
2. temperatureunder reflux for 3 hours
3. customAfter completion of the reaction
4. distillationthe methanol was distilled off under reduced pressure
5. additionWater and ethyl acetate were added to the residue for dissolution
6. customthe organic layer was separated
7. washwashed with saturated aqueous sodium chloride solution
8. dry with materialdried over anhydrous magnesium sulfate
9. concentrationThe organic layer was then concentrated under reduced pressure
10. customthe residue was separated
11. custompurified by silica gel column chromatography (developing solvent: ethyl acetate:n-hexane=1:4)