L-Hydroxyproline → 1-(Phenylmethyl) (2S,4R)-4-hydroxy-1,2-pyrrolidinedicarboxylate

Participants

Reaction Steps

Trans-4-hydroxy-L-proline (4.7 g) was dissolved in 2N sodium hydroxide (36 ml), to which benzyloxycarbonylchloride (6.1 g) was slowly added dropwise under cooling with ice water. The mixture was then stirred at room temperature throughout a whole day and night. After the reaction, the mixture was washed with ethyl acetate, and to the aqueous layer was then added sodium chloride to saturation. Then the pH was adjusted to around 3 with 10N hydrochloric acid and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated solution of sodium chloride in water and it was then dried over anhydrous magnesium sulfate. The solvent was removed under reduced pressure whereby the titled compound (6.9 g) was obtained.

Provenance & Evidence