Reaktion #42283

Reaktionsgleichung

ethyl acetate

potassium hydroxide

tert-Butyl (1S,2S)-3-bromo-1-(3,5-difluorobenzyl)-2-hydroxypropylcarbamate

→

title compound

tert-Butyl (1S)-2-(3,5-difluorophenyl)-1-[(2S)-oxiranyl]ethylcarbamate

Lösungsmittel

ethyl alcohol

—

alcohol

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeThe cold bath is then removed
2. 2
   workup.ADDITIONit is diluted with dichloromethane
3. 3
   Extraktionextracted
4. 4
   Waschenwashed with water, saline
5. 5
   Trocknendried over anhydrous sodium sulfate
6. 6
   Sonstigethe solvent removed under reduced pressure
7. 7
   SonstigeThe crude material is purified by flash chromatography on silica gel

Vorschrift

tert-Butyl (1S,2S)-3-bromo-1-(3,5-difluorobenzyl)-2-hydroxypropylcarbamate (IV, EXAMPLE 2) is dissolved in absolute alcohol (150 mL) and ethyl acetate (100 mL) and potassium hydroxide (2.3 g, 34.9 mmole, 1.1 eq.) in ethyl alcohol (85%, 5 mL) is added at −20 degrees C. The cold bath is then removed and the mixture stirred for 0.5 hour. The reaction is monitored by TLC (ethyl acetate/hexane, 20/80). When the reaction is complete; it is diluted with dichloromethane and extracted, washed with water, saline, dried over anhydrous sodium sulfate and the solvent removed under reduced pressure. The crude material is purified by flash chromatography on silica gel to give the title compound, TLC (ethyl acetate/hexane, 20/80) Rf=0.3; MS (MH+)=300.4.

Quelle