反应详情

温度

-15 °C

To a solution of (S)-4-benzyloxy-2-tert butoxycarbonylamino butyric acid (1.16 g, 3.7 mmol) in anhydrous THF (15 mL) at −15° C. was added N-methylmorpholine (0.41 mL, 3.7 mmol) and isobutylchloroformate (0.51 mL, 3.7 mmol) under a nitrogen atmosphere. After 2 minutes, 33% aqueous ammonia (0.34 mL, 5.6 mmol) was added and the resulting mixture stirred at −15° C. for 2 h. The reaction mixture was left to warm to RT and was partitioned between EtOAc and a saturated aqueous solution of NaHCO3. The combined organic fractions were washed with aqueous 5% NaHCO3, water, dried (MgSO4) and concentrated in vacuo. The resulting white solid was used without further purification (quant. yield). 1H NMR (CDCl3, 300 MHz): δ 7.41-7.25 (5H, m), 6.38 (1H, br s), 5.75 (1H, br s), 5.38 (1H, br s), 4.55-4.45 (2H, m), 4.30 (1H, br s), 3.75-3.52 (2H, m), 2.10-2.00 (2H, m), 1.42 (9H, s).

1. waitThe reaction mixture was left
2. temperatureto warm to RT
3. customwas partitioned between EtOAc
4. washThe combined organic fractions were washed with aqueous 5% NaHCO3, water
5. dry with materialdried (MgSO4)
6. concentrationconcentrated in vacuo
7. customThe resulting white solid was used without further purification (quant. yield)