反应详情

温度

60 °C

At room temperature, a three-neck flask equipped with a reflux condenser, internal thermometer, dropping funnel and stirrer under nitrogen protective gas was initially charged with 7.9 g of zinc powder (121 mmol) in 45 ml of isopropyl acetate. After 1.83 ml of trimethylchlorosilane (12.6 mmol) had been added, the mixture was heated to 60° C. for 15 min, then allowed to cool to 55° C. and 17.7 g of methyl bromoacetate (115 mmol) were added within 5 min, and the temperature of the mixture was maintained at 60° C. by external cooling. The mixture was then stirred at 50° C. for 15 min. After cooling to 40° C., 15.7 g of undiluted 1-phenylhexan-3-one (89 mmol, prepared by base-catalyzed aldol condensation of benzaldehyde and pentan-2-one and subsequent hydrogenation of the 1-phenylhex-1-en-3-one obtained) were added, and the temperature was maintained at 50° C. by external cooling. The mixture was then stirred at 60° C. for 45 min and, after cooling to 15° C., acidified with 20 ml of 20% hydrochloric acid to a pH of 1 and stirred for 30 min. Excess zinc was then filtered off and the organic phase was removed. The organic phase was then stirred with 30 ml of concentrated ammonia solution at 0° C. for 10 min. After the phase separation, drying was effected over sodium sulfate and the solvent was distilled off under reduced pressure. Methyl 3-hydroxy-3-(2-phenylethyl)hexanoate was obtained in a yield of 21.1 g (95% of theory) and a purity of >95% (HPLC).

1. customAt room temperature, a three-neck flask equipped with a reflux condenser
2. temperatureto cool to 55° C.
3. temperaturethe temperature of the mixture was maintained at 60° C. by external cooling
4. temperatureAfter cooling to 40° C.
5. customobtained)
6. additionwere added
7. temperaturethe temperature was maintained at 50° C. by external cooling
8. stirringThe mixture was then stirred at 60° C. for 45 min
9. temperatureafter cooling to 15° C.
10. stirringstirred for 30 min
11. filtrationExcess zinc was then filtered off
12. customthe organic phase was removed
13. stirringThe organic phase was then stirred with 30 ml of concentrated ammonia solution at 0° C. for 10 min
14. customAfter the phase separation
15. customdrying
16. distillationthe solvent was distilled off under reduced pressure