反应详情

温度

33 °C

(2S,3S)-3-tert-butoxycarbonylamino-1-chloro-2-hydroxy-4-phenylbutane (5.29 g) and potassium carbonate (4.88 g) were added to an ethanol:water (97:3) mixed solution (106 ml). The mixture was stirred at 33° C. for 7 hours, and a 10% citric acid aqueous solution (67.8 g) was added thereto. After ethanol was distilled off under reduced pressure, toluene (93 ml) was added to conduct extraction. Further, the organic layer was washed with water (93 ml), and then concentrated. To the residue was added a heptane:toluene (4:1) mixture (112 ml). The heating was conducted at 50° C. over 1 hour, and the stirring was further conducted at 50° C. for 1 hour. Subsequently, cooling was conducted to −10° C. over 5 hours, and stirring was further conducted at −10° C. for 8 hours. Crystals were collected by filtration, washed with heptane, and then dried under reduced pressure to obtain desired (2S,3S)-3-tert-butoxycarbonylamino-1,2-epoxy-4-phenylbutane (4.39 g) in a yield of 95%.

1. distillationAfter ethanol was distilled off under reduced pressure, toluene (93 ml)
2. additionwas added
3. extractionextraction
4. washFurther, the organic layer was washed with water (93 ml)
5. concentrationconcentrated
6. additionTo the residue was added a heptane:toluene (4:1) mixture (112 ml)
7. waitThe heating was conducted at 50° C. over 1 hour
8. waitthe stirring was further conducted at 50° C. for 1 hour
9. temperatureSubsequently, cooling
10. waitwas conducted to −10° C. over 5 hours
11. stirringstirring
12. waitwas further conducted at −10° C. for 8 hours
13. filtrationCrystals were collected by filtration
14. washwashed with heptane
15. customdried under reduced pressure