Sodium Bicarbonate → (2R*,3S*)-3-hydroxy-4,4-dimethyl-2-[(4-phenyl-phenyl)-methoxy-carbonylamino]-pentanoic acid
Reaction equation
[NH2:1][C@H:2]([C@@H:6]([OH:11])[C:7]([CH3:10])([CH3:9])[CH3:8])[C:3]([OH:5])=[O:4].C([O-])(O)=O.[Na+].[C:17](=O)([O-:38])[O:18][C:19]1C(C)=C(C2C=CC(C3C=CC=CC=3)=CC=2)C=CN=1.[C:40]1([C:46]2[CH:51]=[CH:50][C:49](C3C=CN(C([O-])=O)C(=O)C=3C)=[CH:48][CH:47]=2)[CH:45]=[CH:44][CH:43]=[CH:42][CH:41]=1>O.C1COCC1>[OH:11][C@@H:6]([C:7]([CH3:8])([CH3:10])[CH3:9])[C@@H:2]([N:1]([C:49]1[CH:48]=[CH:47][C:46]([C:40]2[CH:41]=[CH:42][CH:43]=[CH:44][CH:45]=2)=[CH:51][CH:50]=1)[C:17]([O:18][CH3:19])=[O:38])[C:3]([OH:5])=[O:4]Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 2
Procedure
To a stirred diastereomeric mixture containing (2R*,3R*)- and (2R*,3S*)-2-amino-3-hydroxy-4,4-dimethyl-pentanoic acid (0.288 g, 1.78 mmol) and NaHCO3 (0.15 g, 1.8 mmol) in H2O (7.0 mL), at rt, the isomeric mixture containing (4-phenylphenyl)-methyl-2-pyridyl carbonate and (4-phenylphenyl)-methyl-2-oxopyridine-1-carboxylate (0.82 g, 2.68 mmol) [prepared as for example 17, step 1] in THF (7.0 mL) was added. After 15 h at rt, the crude mixture was rotary evaporated to remove the organics and subsequently extracted with Et2O (3×10 mL). The aqueous phase was acidified with 2.0 M HCl solution to pH 2-3 and subsequently extracted with AcOEt (3×20 mL). The organic fraction was dried over Na2SO4, filtered and concentrated to dryness to afford the title compound (0.21 g, 32% over 2 steps), as a diastereoisomeric mixture (anti:syn=9:1), as an off-white solid, which was used in the next step without further purification. MS (ESI) m/z: 410 [M−K]+; (ESI) m/z: 370 [M−H]−. 1H NMR (DMSO-d6) δ 0.88 (s, 9H), 3.40 (d, J=7.37 Hz, 1H), 4.09-4.18 (m, 1H), 5.08 (s, 2H), 5.08 (s, broad, 1H), 7.33-7.53 (m, 5H), 7.60 (d, J=8.97 Hz, 1H), 7.63-7.72 (m, 4H), 12.21 (s, 1H) (reported data refer to the major anti diastereoisomer).
Workup
- additionwas added
- customthe crude mixture was rotary evaporated
- customto remove the organics and
- extractionsubsequently extracted with Et2O (3×10 mL)
- extractionsubsequently extracted with AcOEt (3×20 mL)
- dry with materialThe organic fraction was dried over Na2SO4
- filtrationfiltered
- concentrationconcentrated to dryness
Sources & evidence
- ORD record
- ord-0169b71ea16741438d042d78621d7bdf
- Source dataset
- uspto-grants-2016_05
- Patent number
- US09353075B2
Reaction notes
Loading…