反应详情

The pH of a solution of 6.18 g of (S)-3-hydroxy-pyrrolidine hydrochloride in 175 ml of water was adjusted to 10 with 10% sodium hydroxide solution and cooled to 0°-5° C. 7.1 ml of benzyl chloroformate were added dropwise within 30 minutes under argon, with the pH of the solution being held between 9.5 and 11.5 by the dropwise addition of 10% sodium hydroxide solution. After completion of the addition the suspension was stirred at room temperature for 16 hours. The suspension was extracted with ethyl acetate, the organic phase was washed with water, dried over Na2SO4, filtered and the filtrate was concentrated. Purification of the crude product over a silica gel column gave 7.33 g of benzyl (R)-3-hydroxy-pyrrolidine-1-carboxylate as a beige liquid.

1. temperaturecooled to 0°-5° C
2. additionAfter completion of the addition the suspension
3. extractionThe suspension was extracted with ethyl acetate
4. washthe organic phase was washed with water
5. dry with materialdried over Na2SO4
6. filtrationfiltered
7. concentrationthe filtrate was concentrated
8. customPurification of the crude product over a silica gel column