Réaction #3080

Équation de réaction

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

pyridine

thionyl chloride

→

(+)-6,8-dichloro-octanoic acid

Solvants

toluene

toluene

Conditions de réaction

Traitement

1. 1
   TempératureThe mixture was then refluxed for 1 hour
2. 2
   Autrethe organic phase was separated
3. 3
   Lavagewashed with 10 mL of water
4. 4
   Séchagedried over magnesium sulfate
5. 5
   AutreAfter that, the solvent was evaporated under vacuum

Mode opératoire

To a solution of 2.9 g (13.2 mmoles) of the methyl ester of (-)-8-chloro-6-hydroxy-octanoic acid (-)-(VIII), (R=Me) and 0.05 g (0.6 mmoles) of pyridine in 10 ml toluene, 1.9 g (16.2 mmoles) of thionyl chloride in 6 ml toluene were added slowly. The mixture was then refluxed for 1 hour. After cooling to room temperature, the reaction mixture was added to 25 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 2.4 g (81% of the theoretical yield). [α]D20 =+30.1° (c=1, benzene).

Source