反应详情

A solution of EtMgBr (3.0 M in diethylether, 15.1 mL, 45.2 mmol) was added dropwise, to a solution of 5-bromo-1-methyl-1H-imidazole (7.28 g, 45.2 mmol) in dry DCM (40 mL) at 0° C. and stirred for 10 minutes. The mixture was then stirred at room temperature for 30 minutes, cooled in an ice-brine bath and N-methoxy-N,3-dimethyl-4-nitrobenzamide (8.45 g, 37.7 mmol, Intermediate 14: step a) dissolved in 22 mL of DCM was added dropwise. A dark brown solid mass formed. The ice bath was removed and mixture stirred at room temperature for 18 hours. Water was added to the suspension followed by 6 M aqueous HCl slowly to neutralize the mixture (pH=6-7). More DCM was added and layers separated. The organic layer was dried over MgSO4, filtered and concentrated. Et2O was added, the slurry sonicated, and precipitates were filtered and dried to provide the title compound.

1. stirringThe mixture was then stirred at room temperature for 30 minutes
2. temperaturecooled in an ice-brine bath
3. additionwas added dropwise
4. customA dark brown solid mass formed
5. customThe ice bath was removed
6. stirringmixture stirred at room temperature for 18 hours
7. additionWater was added to the suspension
8. additionMore DCM was added
9. customlayers separated
10. dry with materialThe organic layer was dried over MgSO4
11. filtrationfiltered
12. concentrationconcentrated
13. additionEt2O was added
14. customthe slurry sonicated
15. customprecipitates
16. filtrationwere filtered
17. customdried