反应详情

温度

60 °C

Ethylmagnesium bromide (3.0 M solution in diethyl ether, 2.9 mL, 8.7 mmol) was added to a stirred solution of methyl 9-chloro-1-(2,4-dichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazole-6-carboxylate (720 mg, 1.75 mmol) in tetrahydrofuran (7.0 mL), and the mixture was stirred at 60° C. for 2 hr. The reaction was quenched by water, and the mixture was extracted with ethyl acetate. The combined organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel eluting with a 10-50% ethyl acetate/n-hexane gradient mixture. The filtrate was concentrated in vacuo to give the solid, which was recrystallized from ethanol to give the title compound as a colorless crystal (378 mg, 0.861 mmol, 49%).

1. customThe reaction was quenched by water
2. extractionthe mixture was extracted with ethyl acetate
3. washThe combined organic layer was washed with brine
4. dry with materialdried over anhydrous magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue was purified by flash column chromatography on silica gel eluting with a 10-50% ethyl acetate/n-hexane gradient mixture
8. concentrationThe filtrate was concentrated in vacuo
9. customto give the solid, which
10. customwas recrystallized from ethanol