Sodium Hydroxide → (2S,3R)-2,3-epoxy-3-cyclohexylpropionic acid

Participants

Reaction Conditions

Reaction Steps

Into a 2,000 ml three-necked flask equipped with a dropping funnel and a stirrer, the phenyl (2S,3R)-2,3-epoxy-3-cyclohexylpropionate (54.0 g, 219 mmol) obtained in Example 2 and methanol (437 ml) were charged and cooled to 0° C. Then, a 4% sodium hydroxide aqueous solution (250 g, 250 mmol) was added thereto over a period of 1 hour, and the reaction was carried out for further 2 hours at the same temperature. After completion of the reaction, sodium dihydrogenphosphate dihydrate (3.42 g) was added, and then, the solvent was distilled off. Then, water (250 ml) was added, followed by extraction with dichloromethane (50 ml×4 times). Then, sodium dihydrogen phosphate dihydrate (116 g) was added, followed by extraction with ethyl acetate (50 ml×4 times). Then, a 10% hydrochloric acid aqueous solution (200 ml) was added, and the pH was adjusted to 3, followed by extraction with ethyl acetate (50 ml×3 times), drying and concentration, to obtain crude (2S,3R)-2,3-epoxy-3-cyclohexylpropionic acid (20.5 g). The obtained crude product was recrystallized from n-heptane/toluene=2/1 (vol/vol) to obtain the desired (2S,3R)-2,3-epoxy-3-cyclohexylpropionic acid (18.0 g, 106 mmol) (yield: 48%).

Provenance & Evidence