反应详情

温度

70 °C

To a solution of 1-(2,6-dimethylphenyl)-3-(2-methylallyl)-5-oxo-pyrrolidine-3-carboxylic acid methyl ester (prepared from step a, 10.9 g, 36.21 mmol) in MeOH (100 mL) was added 1M LiOH (100 mL, 100 mmol) and the resulting clear solution was refluxed (70° C.) for an hour. The reaction mixture was then cooled to room temperature, MeOH was removed under reduced pressure and the obtained basic aqueous solution was added to a cooled (0° C.) 2N HCl (200 mL) with vigorous stirring. The resulting white solid was filtered, washed with water (3×300 mL), heptane (200 mL) and dried under high vacuum to obtain 1-(2,6-dimethylphenyl)-3-(2-methylallyl)-5-oxo-pyrrolidine-3-carboxylic acid (10 g, quantitative yield). LC-MS: Rt (retention time): 1.98 min, MS: (ES) m/z 288.1 (M+H+).

1. temperatureThe reaction mixture was then cooled to room temperature
2. customMeOH was removed under reduced pressure
3. additionthe obtained basic aqueous solution was added to
4. temperaturea cooled (0° C.) 2N HCl (200 mL) with vigorous stirring
5. filtrationThe resulting white solid was filtered
6. washwashed with water (3×300 mL), heptane (200 mL)
7. customdried under high vacuum