Reaktion #3079

Reaktionsgleichung

(+)-8-chloro-6hydroxy-octanoic acid

pyridine

thionyl chloride

→

(-)-6,8-Dichloro-octanoic acid

Lösungsmittel

toluene

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe mixture was then refluxed for 1 hour
2. 2
   Sonstigethe organic phase was separated
3. 3
   Waschenwashed with 10 mL of water
4. 4
   Trocknendried over magnesium sulfate
5. 5
   SonstigeAfter that, the solvent was evaporated under vacuum

Vorschrift

To a solution of 2.4 g (11.0 mmoles) of the methyl ester of (+)-8-chloro-6hydroxy-octanoic acid (+)-(VIII) (R=Me) and 0.04 g (0.5 mmoles) of pyridine in 8 ml toluene, 1.6 g (13.5 mmoles) of thionyl chloride in 5 ml of toluene were added slowly. The mixture was then refluxed for 1 hour. After cooling to room temperature, the reaction mixture was added to 20 ml ice water and the organic phase was separated and washed with 10 mL of water and dried over magnesium sulfate. After that, the solvent was evaporated under vacuum. The methyl ester of (-)-6,8-Dichloro-octanoic acid (-)-(III), (R=Me) was obtained in a yield of 2.0 g (81% of the theoretical yield). [α]D20 =-30.0° (c=1, benzene).

Quelle