反应详情

温度

-60 °C

4,5-Dibromo-2-methyl-1-((2-(trimethylsilyl)ethoxy)methyl)imidazole (29.2 g) was dissolved in tetrahydrofuran (250 ml), and 1.63N 1-butyl lithium/hexane solution (58.1 ml) was added dropwise over 20 min at from −55° C. to −60° C. The mixture was stirred at −60° C. for 30 min and N,N-dimethylformamide (58 g) was gradually added dropwise at from −55° C. to −60° C. The mixture was stirred at room temperature for 1 hr. Saturated brine was added and the mixture was extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane/ethyl acetate=3/1) to give 4-bromo-2-methyl-1-((2-(trimethylsilyl)ethoxy)methyl)-imidazole-5-carbaldehyde (18.5 g) as a pale-yellow oil.

1. stirringThe mixture was stirred at room temperature for 1 hr
2. extractionthe mixture was extracted with ethyl acetate
3. dry with materialThe organic layer was dried over anhydrous sodium sulfate
4. customthe solvent was evaporated under reduced pressure
5. customThe residue was purified by silica gel column chromatography (hexane/ethyl acetate=3/1)