Methanol → Methyl 1-(4-hydroxyphenyl)-5-oxopyrrolidine-3-carboxylate

반응식

[OH:1][C:2]1[CH:7]=[CH:6][C:5]([N:8]2[C:12](=[O:13])[CH2:11][CH:10]([C:14]([OH:16])=[O:15])[CH2:9]2)=[CH:4][CH:3]=1.[CH3:17]O>S(=O)(=O)(O)O.COC(OC)(C)C>[CH3:17][O:15][C:14]([CH:10]1[CH2:11][C:12](=[O:13])[N:8]([C:5]2[CH:4]=[CH:3][C:2]([OH:1])=[CH:7][CH:6]=2)[CH2:9]1)=[O:16]

참가 물질

실험 절차

The crude (RS)-1-(4-hydroxyphenyl)-5-oxo-pyrrolidine-3-carboxylic acid was dissolved in a mixture of 5000 ml of methanol, 24 ml of concentrated sulfuric acid and 400 ml of 2,2-dimethoxypropane and stirred under reflux for 2 h. The reaction solution was reduced to half of its volume by distillation, then transferred into a 20 l vessel. Under stirring at 40° C., a mixture of 2500 ml of water/ice (1:1) was added. Crystallisation started immediately, and, thereupon, the fine white crystals were collected on a filter funnel. They were washed with a total of 2000 ml of cold water until the filtrate was neutral. The product was dried under reduced pressure to yield 980 g (84% of theory, 2 steps) of (RS)-1-(4-hydroxyphenyl)-5-oxo-pyrrolidine-3-carboxylic acid methyl ester as a white solid; MS: m/e=234 (M+H)+.