Reaktion #166676

Reaktionsgleichung

Na2SO3

H2O2

LiOH—H2O

(S)-tert-butyl 5-((S)-2-((R)-4-benzyl-2-oxooxazolidin-3-yl)-1-(4-bromophenyl)-2-oxo ethyl)-2,2-dimethylpyrrolidine-1-carboxylate

→

(S)-2-(4-bromophenyl)-2-((S)-1-(tert-butoxycarbonyl)-5,5-dimethylpyrrolidin-2-yl)acetic acid

Ausbeute 87.0%

Lösungsmittel

THF water

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe solution was then cooled to 0° C.
2. 2
   workup.STIRRINGThe reaction was stirred at 0° C. for 2 hours
3. 3
   Temperaturto warm to room temperature
4. 4
   workup.STIRRINGstirred overnight
5. 5
   TemperaturThe reaction was then cooled to 0° C.
6. 6
   workup.STIRRINGstirred for 10 minutes
7. 7
   TemperaturThe reaction was then warmed to room temperature
8. 8
   workup.STIRRINGstirred for 10 minutes
9. 9
   EinengenThe reaction was next concentrated
10. 10
    Extraktionextracted with EtOAc (2×20 mL)
11. 11
    Extraktionextracted with DCM (2×20 mL)
12. 12
    TrocknenThe combined DCM fractions were dried over sodium sulfate
13. 13
    Filtrationfiltered
14. 14
    Einengenconcentrated

Vorschrift

30% H2O2 (0.67 mL, 7.0 mmol) was added to a solution of LiOH—H2O (0.24 g, 5.60 mmol) in THF/water (2:1, 93 mL), and the solution was stirred at room temperature for 10 minutes. The solution was then cooled to 0° C. and treated with a solution of (S)-tert-butyl 5-((S)-2-((R)-4-benzyl-2-oxooxazolidin-3-yl)-1-(4-bromophenyl)-2-oxo ethyl)-2,2-dimethylpyrrolidine-1-carboxylate (1.60 g, 2.80 mmol) in THF (10 mL). The reaction was stirred at 0° C. for 2 hours and allowed to warm to room temperature and stirred overnight. The reaction was then cooled to 0° C. and treated with 1M Na2SO3 (10 mL) and stirred for 10 minutes. The reaction was then warmed to room temperature and stirred for 10 minutes. The reaction was next concentrated and extracted with EtOAc (2×20 mL). The aqueous layer was then acidified with 1N HCl to a pH of about 1 to about 2 and extracted with DCM (2×20 mL). The combined DCM fractions were dried over sodium sulfate, filtered, and concentrated to give (S)-2-(4-bromophenyl)-2-((S)-1-(tert-butoxycarbonyl)-5,5-dimethylpyrrolidin-2-yl)acetic acid (1.01 g, 87% yield) as a solid. MS ESI (+) m/z 412 detected.

Quelle