Reaktion #674297

Reaktionsgleichung

(R)-2-methyl-CBS-oxazaborolidine

Me2S

dichloromethane

1-(2,6-dichloro-3-fluorophenyl)ethanone

→

(S)-1-(2,6-dichloro-3-fluorophenyl)ethanol

Lösungsmittel

MeOH

HCl

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONis added
2. 2
   Filtrationthe resulting mixture is filtered through a pad of celite and silica gel
3. 3
   Waschenwashed with 30% EtOAc in hexane
4. 4
   SonstigeThe solvent is removed under reduced pressure
5. 5
   Sonstigethe resulting oil is purified by flash chromatography (20% EtOAc in hexane)

Vorschrift

To (R)-2-methyl-CBS-oxazaborolidine (Aldrich or Callery Chemical Co, 1M in toluene, 1 eq.) at −45° C. is added BH3. Me2S (1.06 eq.). To the previous solution is added at −30° C. a 1M dichloromethane solution of 1-(2,6-dichloro-3-fluorophenyl)ethanone. After completion of the reaction, excess MeOH is added followed by IN HCl. After warming up to room temperature, the resulting mixture is filtered through a pad of celite and silica gel and washed with 30% EtOAc in hexane. The solvent is removed under reduced pressure and the resulting oil is purified by flash chromatography (20% EtOAc in hexane) to afford (S)-1-(2,6-dichloro-3-fluorophenyl)ethanol (optically enriched).

Quelle