Sodium borohydride → (3S)-3-(1-hydroxy-3-methyl-butyl)-pyrrolidine-1-carboxylic acid tert-butyl ester

HRID 1922165Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 1922165
[BH4-].[Na+].[C:3]([O:7][C:8]([N:10]1[CH2:14][CH2:13][C@H:12]([C:15](=[O:20])[CH2:16][CH:17]([CH3:19])[CH3:18])[CH2:11]1)=[O:9])([CH3:6])([CH3:5])[CH3:4]>CO>[C:3]([O:7][C:8]([N:10]1[CH2:14][CH2:13][C@H:12]([CH:15]([OH:20])[CH2:16][CH:17]([CH3:18])[CH3:19])[CH2:11]1)=[O:9])([CH3:6])([CH3:5])[CH3:4]

Komponenten

4

Versuchsvorschrift

Add sodium borohydride (15.2 g, 423 mmol) to a solution of (S)-3-(3-methylbutanoyl)-pyrrolidine-1-carboxylic acid tert-butyl ester (21.6 g, 84.6 mmol) in methanol (500 mL) portion wise and stir at room temperature overnight. Add another equivalent of sodium borohydride (3.04 g, 84.6 mmol). Stir for another 2 hours, evaporate the methanol to half the volume, add brine and extract with EtOAc. Dry the combined organic phases (MgSO4), filter and concentrate under reduced pressure. Separate the diastereoisomers by super critical fluid chromatography (AD-H column) eluting with 10% MeOH/CO2 with 0.2% diethylmethylamine to provide (3S)-3-(1-hydroxy-3-methyl-butyl)-pyrrolidine-1-carboxylic acid tert-butyl ester, isomer 1 (S-1) as the first eluting isomer (8.2 g, 38%) and (3S)-3-(1-hydroxy-3-methyl-butyl)-pyrrolidine-1-carboxylic acid tert-butyl ester, isomer 2 (S-2) as the second eluting isomer (8.9 g, 41%).

Aufarbeitung

  1. stirringStir for another 2 hours
  2. customevaporate the methanol to half the volume
  3. additionadd brine
  4. extractionextract with EtOAc
  5. dry with materialDry the combined organic phases (MgSO4)
  6. filtrationfilter
  7. concentrationconcentrate under reduced pressure
  8. customSeparate the diastereoisomers by super critical fluid chromatography (AD-H column)
  9. washeluting with 10% MeOH/CO2 with 0.2% diethylmethylamine

Quellen und Nachweise

ORD-Eintrag
ord-5d5f54b33a924a45b3b23e55b91edf3e
Quelldatensatz
uspto-grants-2012_05
Patentnummer
US08173821B2

Notizen zur Reaktion

Wird geladen…