(r)-5-Biphenyl-4-ylmethyl-3-[1-diisopropylamino-meth-(e)-ylidene]-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester → (3R,5S)-5-biphenyl-4-ylmethyl-3-methyl-2-oxo-pyrrolidine-1-carboxylic acid tert-butyl ester

HRID 2041643Notes

Reaction equation

HRID 2041643 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].[H][H]>[Pd].CC([O-])=O.CC([O-])=O.[Pb+2].C(OCC)(=O)C>[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

6

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 Lindlar Catalyst (ex Aldrich) is added to the mixture. The mixture is then pressurised under a hydrogen atmosphere to 2 bar. The mixture is stirred at ambient temperature and 2 bar hydrogen pressure for 3 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 99.2:0.8 (3-a, R1=Boc: 3-b, R1=Boc) as determined by hplc.

Workup

  1. filtrationThe mixture is then filtered
  2. customto remove the catalyst
  3. concentrationconcentrated under reduced pressure
  4. customThe residue is then purified by column chromatography (ethyl acetate/hexane, 70:30)

Sources & evidence

ORD record
ord-ee450aa347a04b00adbe8b2402709a24
Source dataset
uspto-grants-2013_11
Patent number
US08580974B2

Reaction notes

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