反应详情

A mixture of of KOH (8.5 g) in ethanol (100 mL) was added at room temperature to benzylmalonic acid diethyl ester (40 g) in ethanol (80 mL) and the solution was stirred at room temperature overnight, then concentrated by evaporation. Water (14 mL) was added and then the mixture was acidified in an ice bath with concentrated hydrochloric acid (12.6 mL). The mixture was partitioned between water and ether; the organic phase was separated, dried and the ether was evaporated. The residue was treated with pyridine (26 mL), piperidine (1.22 g) and paraformaldehyde (3.56 g). The mixture was heated in an oil bath (130°) for 90 minutes, then cooled, and water (440 mL) was added. The mixture was extracted 3 times with n-hexane (150 mL). The combined organic phases were washed successively with water, 1N HCl, water, saturated NaHCO3 solution and brine. The organic solution was dried (MgSO4) and evaporated to give the title compound as colorless oil (26 g, 85 % yield). 1H NMR: 300MHz spectrum consistent with proposed structure.

1. concentrationconcentrated by evaporation
2. additionWater (14 mL) was added
3. customthe mixture was acidified in an ice bath with concentrated hydrochloric acid (12.6 mL)
4. customThe mixture was partitioned between water and ether
5. customthe organic phase was separated
6. customdried
7. customthe ether was evaporated
8. additionThe residue was treated with pyridine (26 mL), piperidine (1.22 g) and paraformaldehyde (3.56 g)
9. temperatureThe mixture was heated in an oil bath (130°) for 90 minutes
10. temperaturecooled
11. additionwater (440 mL) was added
12. extractionThe mixture was extracted 3 times with n-hexane (150 mL)
13. washThe combined organic phases were washed successively with water, 1N HCl, water, saturated NaHCO3 solution and brine
14. dry with materialThe organic solution was dried (MgSO4)
15. customevaporated