反应详情

温度

50 °C

Ethylmagnesium bromide (3.0 M solution in diethyl ether, 14.6 mL, 43.7 mmol) was added to a stirred solution of 1-(2,4-dichlorophenyl)-1,2,3,4-tetrahydropyrimido[1,2-a]benzimidazole-6-carbonitrile (5.00 g, 14.6 mmol) in tetrahydrofuran (50 mL) at 0° C., and the mixture was stirred at 50° C. for 2 hr. The reaction was quenched by methanol, and the mixture was diluted with aqueous saturated ammonium chloride and extracted with ethyl acetate. The combined organic layer was washed with brine, dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo. A mixture of the resulting imine, acetic acid (10 mL) and 1N hydrochloric acid (20 mL) was stirred at 50° C. for 2 hr. The mixture was concentrated in vacuo, diluted with saturated aqueous sodium hydrogen carbonate and 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 recrystallized from ethyl acetate/diisopropyl ether to give the title compounds as a colorless crystal (3.04 g, 8.12 mmol, 56%).

1. customThe reaction was quenched by methanol
2. additionthe mixture was diluted with aqueous saturated ammonium chloride
3. extractionextracted with ethyl acetate
4. washThe combined organic layer was washed with brine
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. additionA mixture of the resulting imine, acetic acid (10 mL) and 1N hydrochloric acid (20 mL)
9. stirringwas stirred at 50° C. for 2 hr
10. concentrationThe mixture was concentrated in vacuo
11. additiondiluted with saturated aqueous sodium hydrogen carbonate
12. extractionextracted with ethyl acetate
13. washThe combined organic layer was washed with brine
14. dry with materialdried over anhydrous magnesium sulfate
15. filtrationfiltered
16. concentrationconcentrated in vacuo
17. customThe residue was recrystallized from ethyl acetate/diisopropyl ether