反应详情

Sodium (0.5 g) was dissolved in ethanol (7 ml) and diethyl propylmalonate (4.4 g) was added to the solution. The resulting mixture was heated under reflux for 15 minutes. To the mixture was added N-(5-bromopentyl)phthalimide (6.4 g) and the mixture was further heated under reflux for 4 hours. Then, ethanol was removed by distillation. The residue was treated with ether and filtered. The filtrate was concentrated and the residue was chromatographed on silica gel column. A fraction eluted with 5% methanol in chloroform was recrystallized from a mixture of ether and hexane to give colorless crystals of diethyl 2-(5-phthalimidopentyl)-2-propylmalonate (m.p. 51°-52° C., yield 3.7 g).

1. temperatureThe resulting mixture was heated
2. temperatureunder reflux for 15 minutes
3. temperaturethe mixture was further heated
4. temperatureunder reflux for 4 hours
5. customThen, ethanol was removed by distillation
6. additionThe residue was treated with ether
7. filtrationfiltered
8. concentrationThe filtrate was concentrated
9. customthe residue was chromatographed on silica gel column
10. washA fraction eluted with 5% methanol in chloroform
11. customwas recrystallized from a mixture of ether and hexane