Methanol → 4-Hydroxy-L-proline methyl ester hydrochloride

Participants

Reaction Steps

Thionyl chloride (11.6 ml, 160 mmol) was added to a stirred solution of (2S,4R)-4-hydroxypyrrolidine-2-carboxylic acid (10.0 g, 76.26 mmol) (1) in methanol (150 ml) at −78° C. for 10 min. The mixture was then stirred in an ice bath for 30 minutes followed by stirring at RT for 30 min. Finally the mixture was refluxed for three hours and concentrated in vacuo to give (2S,4R)-methyl 4-hydroxypyrrolidine-2-carboxylate hydrochloride (2) (17.90 g, 95%) as a white solid. Used without further purification. MS m/z 146.2 (M+H)+; retention time=0.19 min, method [1].

Provenance & Evidence