反应详情

To a THF (14 ml) solution of (S)-1-(tert-butoxycarbonyl)pyrrolidine-2-carboxylic acid (0.557 g) and Et3N (0.790 ml), ethyl chloroformate (0.295 g) was added over an ice bath, followed by stirring at the same temperature for 30 minutes. The reaction mixture was added at 0° C. to a THF (7 ml) solution of the compound (0.701 g) obtained in Example 19-(3) and the mixture was stirred at room temperature for 17 hours. After adding water and performing extraction with AcOEt, the organic layer was washed with saturated aqueous sodium chloride, dried (MgSO4), filtered and concentrated to give a crude product, which was further purified by silica gel chromatography (AcOEt/hexane) to give the titled compound (0.540 g, brown amorphous.)

1. stirringthe mixture was stirred at room temperature for 17 hours
2. extractionextraction with AcOEt
3. washthe organic layer was washed with saturated aqueous sodium chloride
4. dry with materialdried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated
7. customto give a crude product, which
8. customwas further purified by silica gel chromatography (AcOEt/hexane)