Ethyl Acetate → (3R,5S)-5-biphenyl-4-ylmethyl-3-methyl-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester
Reaction equation
[C:1]([O:5][C:6]([N:8]1[C@H:12]([CH2:13][C:14]2[CH:19]=[CH:18][C:17]([C:20]3[CH:25]=[CH:24][CH:23]=[CH:22][CH:21]=3)=[CH:16][CH:15]=2)[CH2:11]/[C:10](=[CH:26]\N(C(C)C)C(C)C)/[C:9]1=[O:34])=[O:7])([CH3:4])([CH3:3])[CH3:2].C(OCC)(=O)C.[H][H]>[Pd].O>[C:1]([O:5][C:6]([N:8]1[C@H:12]([CH2:13][C:14]2[CH:15]=[CH:16][C:17]([C:20]3[CH:21]=[CH:22][CH:23]=[CH:24][CH:25]=3)=[CH:18][CH:19]=2)[CH2:11][C@@H:10]([CH3:26])[C:9]1=[O:34])=[O:7])([CH3:4])([CH3:2])[CH3:3].[C:1]([O:5][C:6]([N:8]1[C@H:12]([CH2:13][C:14]2[CH:15]=[CH:16][C:17]([C:20]3[CH:21]=[CH:22][CH:23]=[CH:24][CH:25]=3)=[CH:18][CH:19]=2)[CH2:11][C@H:10]([CH3:26])[C:9]1=[O:34])=[O:7])([CH3:4])([CH3:2])[CH3:3]Participants
Reactant 3
Product 2
Reagents, catalysts & solvents 2
Procedure
1.3 g (R)-5-Biphenyl-4-ylmethyl-3-[1-dimethylaminometh-(E/Z)-ylidene]-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (7-a, R1=Boc, R6=Me, R7=Me) is added to ethyl acetate (40 ml) at ambient temperature. 0.3 g of 10% Palladium on Carbon (Engelhard 4505) and water (0.3 ml) is added to the mixture. The mixture is then pressurised under a hydrogen atmosphere to 4 bar. The mixture is stirred at ambient temperature and 4 bar hydrogen pressure for 4 days. The mixture is then filtered to remove the catalyst and concentrated under reduced pressure. The residue is then purified by column chromatography (ethyl acetate/hexane, 70:30) to afford (3R,5S)-5-biphenyl-4-ylmethyl-3-methyl-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (3-a, R1=Boc) and (3S,5S)-5-biphenyl-4-ylmethyl-3-methyl-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester (3-b, R1=Boc). Diastereomer ratio 67:33 (3-a, R1=Boc:3-b, R1=Boc) as determined by hplc.
Workup
- filtrationThe mixture is then filtered
- customto remove the catalyst
- concentrationconcentrated under reduced pressure
- customThe residue is then purified by column chromatography (ethyl acetate/hexane, 70:30)
Sources & evidence
- ORD record
- ord-9332fe828f07400a813a8f78a1bc4cca
- Source dataset
- uspto-grants-2016_08
- Patent number
- US09403766B2
Reaction notes
Loading…