反应详情

Potassium permanganate (30.1 g) and sodium hydroxide (15.3 g) were added to a solution of dimethylformamide (380 ml) and pyridine (300 ml), and 1-(4-fluorophenyl)-2-formylpyrrole (30 g) was further added thereto under ice-cooling with stirring. The mixture was warmed to room temperature and stirred further for 3 h. The reaction mixture was filtrated and the filtrate was neutralized with hydrochloric acid. The precipitated crystals were recrystallized from hydrous ethanol to give 1-(4-fluorophenyl)pyrrole-2-carboxylic acid (20 g), melting point 195–196° C.

1. additionwas further added
2. temperatureunder ice-cooling
3. stirringstirred further for 3 h
4. filtrationThe reaction mixture was filtrated
5. customThe precipitated crystals were recrystallized from hydrous ethanol