反应详情

5-(2-Hydroxy-4-nitroanilinocarbonyl)-2-methyl-1-(tetrahydropyran-4-yl)benzimidazole (see Working Example 47-1) (195 mg, 0.492 mmol) was added to toluene (20 mL), after which p-toluenesulfonic acid hydrate (280 mg, 1.47 mmol) was added and this was refluxed with stirring for 4 hours. After the solvent was concentrated under reduced pressure, a sodium bicarbonate water (10 mL) was added and this was stirred at room temperature for 1 hour. The precipitated crystals were filtered off, and after being washed with water were dried with heating at reduced pressure to yield the title compound (144 mg, 77.4% yield) as a pale yellow solid.

1. temperaturethis was refluxed
2. concentrationAfter the solvent was concentrated under reduced pressure
3. additiona sodium bicarbonate water (10 mL) was added
4. stirringthis was stirred at room temperature for 1 hour
5. filtrationThe precipitated crystals were filtered off
6. washafter being washed with water
7. customwere dried
8. temperaturewith heating at reduced pressure