反应详情

Into a 100 ml three-necked round-bottomed flask equipped with a dropping funnel and a stirrer, the (S)-2,3-epoxy-2-trifluoromethylpropionic acid phenyl ester (7.2 g, 31.0 mmol) obtained in Example 7, methanol (20 ml) and water (20 ml) were charged and cooled to 0° C. on an ice bath, whereupon 3N sodium hydroxide aqueous solution (30 ml, 90 mmol) was dropwise added over a period of one hour by means of the dropping funnel, and stirring was further carried out at the same temperature for one hour. After completion of the reaction, methanol was distilled off, followed by extraction with diisopropyl ether (30 ml×twice). Then, hydrochloric acid was added to adjust the pH to 3, followed by extraction with ethyl acetate (30 ml×3 times). The obtained organic layer was dried over anhydrous magnesium sulfate, followed by filtration and concentration to obtain the desired (S)-2,3-epoxy-2-trifluoromethylpropionic acid (4.17 g, 26.7 mmol, yield: 87%, optical purity: 78% ee).

1. customInto a 100 ml three-necked round-bottomed flask equipped with a dropping funnel and a stirrer
2. additionwas dropwise added over a period of one hour by means of the dropping funnel
3. distillationwas distilled off
4. extractionfollowed by extraction with diisopropyl ether (30 ml×twice)
5. additionThen, hydrochloric acid was added
6. extractionfollowed by extraction with ethyl acetate (30 ml×3 times)
7. dry with materialThe obtained organic layer was dried over anhydrous magnesium sulfate
8. filtrationfollowed by filtration and concentration