反应详情

To a stirred solution of 2-tert-butoxycarbonylamino-5-((S)-2-methoxymethyl-pyrrolidin-1-yl)-5-oxo-pentanoic acid methyl ester (0.72 g, 2 mmol) in CH3OH (20 mL) was added 2 N aqueous sodium hydroxide (20 mL). After stirred at room temperature for 12 h, the mixture was acidified by the addition of 6 N aqueous hydrochloric acid at 0° C. to pH=4. Most of methanol was removed under reduced pressure and the residue was partitioned between CH2Cl2 (20 mL) and H2O (20 mL). The aqueous layer was further extracted with CH2Cl2 (20 mL). The combined organic layers were dried over magnesium sulfate, filtered, and concentrated under reduced pressure to yield the title compound (0.54 g, 79%) as a foamy solid which was used in the next step without further purification.

1. customMost of methanol was removed under reduced pressure
2. customthe residue was partitioned between CH2Cl2 (20 mL) and H2O (20 mL)
3. extractionThe aqueous layer was further extracted with CH2Cl2 (20 mL)
4. dry with materialThe combined organic layers were dried over magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure