反应详情

温度

55 °C

A mixture of (2S,3S)-3-amino-2-(tert-butoxycarbonylamino)butanoic acid (3.14 g, 14.4 mmol), dimethylsulfoxide (40 ml), 3-fluoro-4-nitrobenzonitrile (2.63 g, 15.8 mmol), and sodium bicarbonate (4.83 g, 57.5 mmol) was stirred at 55° C. for 3 h. Additional NaHCO3 (0.9 g) was added and the mixture was stirred at 60° C. for 1 hour, then cooled to RT, diluted with cold sat. Na2CO3, and washed with MTBE. The aqueous phase was carefully acidified to pH ˜4 with solid citric acid and extracted with EtOAc (three times). The combined organic layers were washed with H2O twice and brine, dried over Na2SO4, filtered, and concentrated to provide (2S,3S)-2-(tert-butoxycarbonylamino)-3-(5-cyano-2-nitrophenylamino)butanoic acid (5.7 g, quant.).

1. stirringthe mixture was stirred at 60° C. for 1 hour
2. temperaturecooled to RT
3. washwashed with MTBE
4. extractionextracted with EtOAc (three times)
5. washThe combined organic layers were washed with H2O twice
6. dry with materialbrine, dried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated