反应详情

温度

5 °C

First, 18.00 g (100 mmol) of 2-mercapto-5-methoxy-1H-benzimidazole, 16.83 g (300 mmol) of potassium hydroxide, 75 ml of ethanol, and 50 ml of water were added to a 3-necked flask (300 ml volume) equipped with a thermometer, a mechanical stirrer and a dropping funnel, and cooled to 5° C. Next, 15.00 g (105 mmol) of iodomethane was added dropwise to this solution over a period of 30 minutes while keeping internal temperature at 10° C. or lower. Then the solution was agitated for 2 hours at 10° C. or lower. The reaction solution was neutralized with an aqueous 2N hydrochloric acid solution, then the ethanol was removed under reduced pressure to precipitate a colorless solid. This solid was filtered and dried under reduced pressure to give 19.19 g of 2-methylthio-5-methoxy-1H-benzimidazole (yield of 98.9%).

1. customequipped with a thermometer, a mechanical stirrer and a dropping funnel
2. customat 10° C.
3. customthe ethanol was removed under reduced pressure
4. customto precipitate a colorless solid
5. filtrationThis solid was filtered
6. customdried under reduced pressure