Citric Acid → (2S,3S)-(-)-3-tert-Butoxycarbonylamino-1,2-epoxy-4-phenylbutane

Participants

Reaction Conditions

Reaction Steps

(2S,3S)-3-tert-butoxycarbonylamino-1-chloro-2-hydroxy-4-phenylbutane (3.57 g) and potassium carbonate (3.29 g) were added to an ethanol:water (97:3) mixed solution (35.7 ml). The mixture was stirred at 27° C. for 22 hours and further at 33° C. for 4 hours. A 11.3% citric acid aqueous solution (40.3 g) was added thereto, and the cooling was then conducted to −10° C. Crystals were collected by filtration, washed with water (35.7 ml), and dried under reduced pressure to obtain desired (2S,3S)-3-tert-butoxycarbonylamino-1,2-epoxy-4-phenylbutane (2.88 g) in a yield of 95%.

Provenance & Evidence