Réaction #61114

Équation de réaction

oxazolidinone

n-butyllithium

(S)-(+)-4-phenyl-2-oxazolidinone

Triethylamine

(S)-3-phenylbutyric acid

pivaloyl chloride

→

(S)-4-phenyl-3-((S)-3-phenyl-butyryl)-oxazolidin-2-one

Rendement 88.0%

Solvants

tetrahydrofuran

tetrahydrofuran

Conditions de réaction

Traitement

1. 1
   Autreto give a white solid
2. 2
   Températurethen cooled back down to −78° C
3. 3
   workup.STIRRINGstirring
4. 4
   workup.WAITcontinued for 2 hours
5. 5
   AutreThe reaction was quenched with water (25 mL)
6. 6
   Extractionextracted with ethyl acetate
7. 7
   LavageThe combined extracts were washed with water, brine
8. 8
   Séchagedried over sodium sulfate
9. 9
   AutreThe crude product was purified by chromatography over silica gel
10. 10
    Lavageeluted with 2:3 ethyl acetate/hexanes
11. 11
    Autrethe resulting solid was recrystallized from ethyl acetate/hexanes

Mode opératoire

Triethylamine (1.3 mL, 9.1 mmol) was added to (S)-3-phenylbutyric acid (1.0 g, 6.1 mmol) in anhydrous tetrahydrofuran (60 mL) at −78° C. followed by the dropwise addition of pivaloyl chloride (0.83 ml, 6.7 mmol) to give a white solid. The reaction was allowed to warm to room temperature for 10 minutes then cooled back down to −78° C. In a separate flask, n-butyllithium (4.6 mL, 11.6 mmol, 2.5 M F in hexanes) was added to (S)-(+)-4-phenyl-2-oxazolidinone (2.0 g, 12.2 mmol) in anhydrous tetrahydrofuran at −78° C. and allowed to stir for 10 minutes. The lithiated oxazolidinone was transfered via cannula to the mixed anhydride at −78° C. and stirring continued for 2 hours. The reaction was quenched with water (25 mL) and extracted with ethyl acetate. The combined extracts were washed with water, brine and dried over sodium sulfate. The crude product was purified by chromatography over silica gel eluted with 2:3 ethyl acetate/hexanes and the resulting solid was recrystallized from ethyl acetate/hexanes to afford (S)-4-phenyl-3-((S)-3-phenyl-butyryl)-oxazolidin-2-one (1.63 g, 88% yield).

Source