Ammonium Hydroxide → tert-butyl (2S,3R)-4-amino-3-hydroxy-1-phenylbutan-2-ylcarbamate

HRID 2071180Notes

Reaction equation

HRID 2071180 reaction equation
[O:1]1[CH2:3][C@@H:2]1[C@@H:4]([NH:12][C:13](=[O:19])[O:14][C:15]([CH3:18])([CH3:17])[CH3:16])[CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1.[NH4+:20].[OH-]>CCO>[NH2:20][CH2:3][C@@H:2]([OH:1])[C@@H:4]([NH:12][C:13](=[O:19])[O:14][C:15]([CH3:18])([CH3:17])[CH3:16])[CH2:5][C:6]1[CH:11]=[CH:10][CH:9]=[CH:8][CH:7]=1

Participants

4

Reactant 2

HCID 14923Ammonium HydroxideHCID 9903372(2S,3S)-(-)-3-tert-Butoxycarbonylamino-1,2-epoxy-4-phenylbutane

Product 1

HCID 10333883tert-butyl (2S,3R)-4-amino-3-hydroxy-1-phenylbutan-2-ylcarbamate

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A solution of tert-butyl (S)-1-((S)-oxiran-2-yl)-2-phenylethylcarbamate (1.5 g, 5.7 mmol) in EtOH (35 mL) was added, with stirring, over 1 h to NH4OH (35 mL) at 0° C. NH3 gas was bubbled through the reaction mixture during the addition and for 1 h afterward. The reaction mixture was allowed to warm to room temperature and stirred overnight. The resulting slurry was diluted with EtOAc (80 mL), and the organic layer was washed with brine and dried (MgSO4). Concentration in vacuo, followed by trituration with 10% i-PrOH-EtOAc (overnight stirring), afforded tert-butyl (2S,3R)-4-amino-3-hydroxy-1-phenylbutan-2-ylcarbamate (0.44 g) as a white solid. The mother liquors were concentrated in vacuo and triturated again as above to give an additional quantity of tert-butyl (2S,3R)-4-amino-3-hydroxy-1-phenylbutan-2-ylcarbamate (0.57 g; 64% total yield): 1H NMR (CD3OD) d: 1.29 (s, 9H), 2.55 (m, 1H), 2.63 (m, 1H), 2.76 (m, 1H), 3.11 (m, 1H), 3.40 (m, 1H), 3.65 (m, 1H), 7.10-7.30 (m, 5H).

Workup

  1. customNH3 gas was bubbled through the reaction mixture during the addition and for 1 h afterward
  2. additionThe resulting slurry was diluted with EtOAc (80 mL)
  3. washthe organic layer was washed with brine
  4. dry with materialdried (MgSO4)
  5. concentrationConcentration in vacuo
  6. customfollowed by trituration with 10% i-PrOH-EtOAc (overnight stirring)

Sources & evidence

ORD record
ord-f96b047662024263b3b4dabf4bc3f458
Source dataset
uspto-grants-2012_10
Patent number
US08299267B2

Reaction notes

Loading…