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 15.1 g of zinc powder (231 mmol) in 90 ml of isopropyl acetate. After 3.7 ml of trimethylchlorosilane (29 mmol) had been added, the mixture was heated to 60° C. for 20 min, then allowed to cool to 55° C. and 32.6 g of undiluted methyl bromoacetate (213 mmol) were subsequently added dropwise within 10 min, and the temperature was maintained at 60° C. by external cooling. The mixture was then stirred at 50° C. for 15 min. After cooling to 5° C., 21.3 g of undiluted styrene oxide (178 mmol) were added, and the temperature was maintained at 5° C. by external cooling. After stirring had been continued at 5° C. for 30 min, the mixture was heated to 25° C. within 20 min and stirred at this temperature for a further 30 min. After cooling to 0° C., the mixture was acidified using 33 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 removed. The organic phase was then stirred at 0° C. with 40 ml of 1 N hydrochloric acid and finally washed with 20 ml of concentrated ammonia solution. After the phase separation, drying was effected over sodium sulfate and the solvent was distilled off under reduced pressure (>90% of the solvent isopropyl acetate was recovered). After distillation, methyl 4-hydroxy-4-phenylbutyrate was obtained in a yield of 30.9 g (90% of theory) and had a boiling point of 128° C. (4 mbar).

1. customAt room temperature, a three-neck flask equipped with a reflux condenser
2. temperatureto cool to 55° C.
3. temperaturethe temperature was maintained at 60° C. by external cooling
4. temperatureAfter cooling to 5° C.
5. temperaturethe temperature was maintained at 5° C. by external cooling
6. stirringAfter stirring
7. waithad been continued at 5° C. for 30 min
8. temperaturethe mixture was heated to 25° C. within 20 min
9. stirringstirred at this temperature for a further 30 min
10. temperatureAfter cooling to 0° C.
11. stirringstirred for 30 min
12. filtrationExcess zinc was then filtered off
13. customthe organic phase removed
14. stirringThe organic phase was then stirred at 0° C. with 40 ml of 1 N hydrochloric acid
15. washfinally washed with 20 ml of concentrated ammonia solution
16. customAfter the phase separation
17. customdrying
18. distillationthe solvent was distilled off under reduced pressure (>90% of the solvent isopropyl acetate was recovered)
19. distillationAfter distillation