反应详情

2-[{4-(3-Methoxypropoxy)-3-methylpyridin-2-yl}methylthio]-1H-benzimidazole (25.0 g (72.8 mmol)) was dissolved in dichloromethane, and then the solution was cooled, and mcpba (70.2% purity; 7.16 g (29.1 mmol)) was added little by little such that the internal temperature did not exceed −15° C. After the addition, a 10% sodium hydroxide aqueous solution (70.8 ml) was added, the mixture was stirred and then left to stand, and then the aqueous layer was separated off. The separated aqueous layer was washed twice with dichloromethane (48 ml). A 2N ammonium acetate aqueous solution was then put into the solution, and then extraction was carried out twice with dichloromethane (48 ml). The dichloromethane layers were washed twice with water (48 ml), vacuum concentration was carried out, crystallization was carried out using dichloromethane (18 ml) and acetone (120 ml), and then filtration was carried out, thus obtaining 2-[{4-(3-methoxypropoxy)-3-methylpyridin-2-yl}methylsulfinyl]-1H-benzimidazole (8.56 g) (HPLC purity 99.7%, yield 32.7%).

1. temperaturethe solution was cooled
2. additionmcpba (70.2% purity; 7.16 g (29.1 mmol)) was added little by little such that the internal temperature
3. customdid not exceed −15° C
4. additionAfter the addition
5. waitleft
6. customthe aqueous layer was separated off
7. washThe separated aqueous layer was washed twice with dichloromethane (48 ml)
8. extractionextraction
9. washThe dichloromethane layers were washed twice with water (48 ml), vacuum concentration
10. customcrystallization
11. filtrationfiltration