反应详情

345 g of acetic anhydride was added dropwise to a suspension of 600 g of 4-hydroxy-L-proline ethyl ester hydrochloride, 683 g of triethylamine and 2.4 L of chloroform at not higher than 10° C. while cooling. After stirring for 2 hours, water (0.6 L) was added, and the layers were separated. The organic layer was dried over magnesium sulfate, and concentrated under reduced pressure to obtain 1020 g of N-acetyl-4-hydroxy-L-proline ethyl ester as an oil.

1. temperaturewhile cooling
2. customthe layers were separated
3. dry with materialThe organic layer was dried over magnesium sulfate
4. concentrationconcentrated under reduced pressure