反应详情

To a solution of (−)-1-[9-chloro-1-(2,4-dichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazol-6-yl]propyl acetate (79.6 mg, 0476 mmol) in methanol (1.5 mL) was added potassium carbonate (36.4 mg, 0.264 mmol). The reaction mixture was stirred at room temperature for 1 hr. After the mixture was concentrated, the residue was diluted with water and extracted with ethyl acetate (×3). The combined organic layer was washed with brine (×1), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel column chromatography eluting with a 0-50% ethyl acetate/n-hexane gradient mixture. The resulting solid was recrystallized from ethyl acetate/n-hexane to give the title compound as a colorless powder (51.1 mg, 0.124 mmol, 71%).

1. concentrationAfter the mixture was concentrated
2. additionthe residue was diluted with water
3. extractionextracted with ethyl acetate (×3)
4. washThe combined organic layer was washed with brine (×1)
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe residue was purified by silica gel column chromatography
9. washeluting with a 0-50% ethyl acetate/n-hexane gradient mixture
10. customThe resulting solid was recrystallized from ethyl acetate/n-hexane