反应详情

温度

80 °C

The 4-(5-phenoxybenzimidazole-2-yl)-3,5-dimethylpyrrole-2-carboxylic acid ethyl ester (1.88 g, 5.0 mmol) obtained in Example 68 was dissolved in ethanol (10 ml) and tetrahydrofuran (5 ml). To this solution was added a 4 N sodium hydroxide aqueous solution (6 ml, 24 mmol), and the mixture was stirred at 80° C. for 6 hours. The reaction mixture was cooled to 0° C., and neutralized with a 1 N hydrochloric acid solution. The precipitate was collected by filtration, and washed with water and dried at reduced pressure to afford 4-(5-phenoxybenzimidazole-2-yl)-3,5-dimethylpyrrole-2-carboxylic acid (1.70 g, 98%) as a light yellow solid.

1. temperatureThe reaction mixture was cooled to 0° C.
2. filtrationThe precipitate was collected by filtration
3. washwashed with water
4. customdried at reduced pressure