Ammonia → tert-Butyl (S)-(1-amino-1-oxobutan-2-yl)carbamate
Reaction equation
[C:1]([O:5][C:6]([NH:8][C@@H:9]([CH2:13][CH3:14])[C:10](O)=[O:11])=[O:7])([CH3:4])([CH3:3])[CH3:2].C[N:16]1CCOCC1.C(OC(Cl)=O)C(C)C.N>C1COCC1>[C:1]([O:5][C:6](=[O:7])[NH:8][C@H:9]([C:10](=[O:11])[NH2:16])[CH2:13][CH3:14])([CH3:4])([CH3:3])[CH3:2]Participants
Conditions
- Temperature
- -15 °C
Procedure
To a solution of (S)-2-tertbutoxycarbonylamino butyric acid (1.2 g, 5.8 mmol) in anhydrous THF (20 mL) cooled to −15° C. was added N-methylmorpholine (0.64 mL, 5.8 mmol) and isobutylchloroformate (0.75 mL, 5.8 mmol) under an atmosphere of nitrogen. After 2 minutes, 33% aqueous ammonia (0.5 mL, 8.7 mmol) was added and the resulting mixture stirred at this −15° C. for 2 h. The reaction mixture was left to warm to RT then 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 (1.0 g, 85%). 1H NMR (CDCl3, 300 MHz): δ 6.15 (1H, br s), 5.63 (1H, br s), 5.08 (1H, br s), 4.05 (1H, br s), 1.95-1.80 (1H, m), 1.70-1.53 (1H, m), 1.40 (9H, s), 0.95 (3H, d, J=6.71 Hz). 327997
Workup
- waitThe reaction mixture was left
- temperatureto warm to RT
- customthen partitioned between EtOAc
- washThe combined organic fractions were washed with aqueous 5% NaHCO3, water
- dry with materialdried (MgSO4)
- concentrationconcentrated in vacuo
- customThe resulting white solid was used without further purification (1.0 g, 85%)
Sources & evidence
- ORD record
- ord-b32ab4296a694a3b9e13d1279f4ee1ab
- Source dataset
- uspto-grants-2014_02
- Patent number
- US08653089B2
Reaction notes
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