反应详情

温度

50 °C

4-(2-Methoxycarbonyl-ethyl)-3,5-dimethyl-1H-pyrrole-2-carboxylic acid ethyl ester (Aldrich, 228 g, 0.9 mol) and 720 mL of 5 N sodium hydroxide were refluxed for one hour. Thin layer chromatography showed the hydrolysis to be complete. The stirred mixture was cooled to 50° C. and hydrochloric acid (10 N, 390 mL) was slowly added to give a pH of 2-3. The oil which separated solidified. The mixture was stirred and cooled to 4° C. The solids were collected by vacuum filtration, washed thoroughly with water and dried under vacuum at 40° C. to give 65.7 g (49% yield) of 3-(2,4-dimethyl-1H-pyrrol-3-yl)-propionic acid as a reddish solid.

1. customthe hydrolysis
2. customto give a pH of 2-3
3. customThe oil which separated
4. temperaturecooled to 4° C
5. filtrationThe solids were collected by vacuum filtration
6. washwashed thoroughly with water
7. customdried under vacuum at 40° C.