反应详情

温度

-40 °C

To a solution of 4-benzyl 3-tert-butyl(4S,5R)-5-methyl-1,2,3-oxathiazolidine-3,4-dicarboxylate 2,2-dioxide (17.13 g, 46.1 mmol) in DMF (171 ml) at −40° C. was added sodium azide (3.9 g, 60.0 mmol) in portions, and the mixture was stirred at −40° C. then slowly warmed to rt over 4 h. Added 20% aq. NaCl (100 ml), followed by dropwise addition of 2 N H2SO4 (10 ml). The reaction was stirred at rt for 3 h, then partitioned between H2O and EtOAc, and the aqueous layer was extracted with EtOAc. The combined organic layers were washed with H2O and brine, dried over Na2SO4, filtered, and concentrated to afford (2S,3S)-benzyl 3-azido-2-(tert-butoxycarbonylamino)butanoate as a slightly yellowish glue (14.8 g, 96%).

1. temperaturethen slowly warmed to rt over 4 h
2. stirringThe reaction was stirred at rt for 3 h
3. custompartitioned between H2O and EtOAc
4. extractionthe aqueous layer was extracted with EtOAc
5. washThe combined organic layers were washed with H2O and brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated