反应详情

Ethyl acetoacetate (53.8 g., 0.29 mole) was dissolved in 110 ml. of anhydrous ethanol. Sodium methoxide (17.3 g., 0.36 mole) was added portionwise to the stirred solution, allowing the temperature to rise to 40°-50°. The mixture was then heated to reflux (80°-82°) and phenethyl bromide (53.8 g., 0.32 mole) added dropwise over 1 hour. Reflux was continued for 20 hours. The reaction mixture was cooled to 30°-35° and filtered over diatomaceous earth with ethanol wash. The combined filtrate and wash were concentrated in vacuo to a pot temperature of 50°, cooled to 25°, diluted with 150 ml. of hexane and 40 ml. of water, acidified to pH 6.5-7.0 with 6N HCl. The hexane layer was separated and washed with 25 ml. of fresh water. The aqueous layers were combined and back-washed with 40 ml. of fresh hexane. The hexane layers were combined, washed with 60 ml. of water, dried over 15 g. MgSO4, filtered and evaporated to yield title product as an oil (62 g., 91%).

1. customto rise to 40°-50°
2. temperatureThe mixture was then heated
3. additionadded dropwise over 1 hour
4. temperatureReflux
5. temperatureThe reaction mixture was cooled to 30°-35°
6. filtrationfiltered over diatomaceous earth with ethanol
7. washwash
8. washThe combined filtrate and wash
9. concentrationwere concentrated in vacuo to a pot temperature of 50°
10. temperaturecooled to 25°
11. additiondiluted with 150 ml
12. customThe hexane layer was separated
13. washwashed with 25 ml
14. washback-washed with 40 ml
15. washwashed with 60 ml
16. dry with materialof water, dried over 15 g
17. filtrationMgSO4, filtered
18. customevaporated