Reaction #481599

Reaction equation

thionyl chloride

4-hydroxyproline

ethanol

→

4hydroxy-L-proline ethyl ester hydrochloride

Conditions

Workup

1. 1
   Otherequipped with an addition funnel
2. 2
   TemperatureThe flask was then cooled in a dry ice/acetone bath
3. 3
   OtherThe funnel was removed
4. 4
   OtherThe flask was equipped with a reflux condenser and a sodium hydroxide trap
5. 5
   Temperaturethe mixture was refluxed for two hours
6. 6
   OtherThe product was precipitated in ether
7. 7
   Otherisolated by filtration
8. 8
   Washwashed three times with ether
9. 9
   Otherit was dried under a stream of nitrogen

Procedure

200 mL of absolute ethanol were placed in a 500-mL one-necked round-bottomed flask equipped with an addition funnel. The flask was then cooled in a dry ice/acetone bath, then 17 mL (0.23 mmoles) of thionyl chloride were added from the addition funnel over a 10 minute period. The funnel was removed, and 26.2 g (0.20 mmoles) of 4-hydroxyproline were added in one portion while stirring. The flask was equipped with a reflux condenser and a sodium hydroxide trap, and the mixture was refluxed for two hours. The product was precipitated in ether, isolated by filtration, and washed three times with ether, then it was dried under a stream of nitrogen followed by high vacuum.

Source