反应详情

温度

90 °C

4-Bromo-2-ethyl-1-(methoxymethyl)imidazole-5-carbaldehyde (365 g) was dissolved in 35% conc. hydrochloric acid (1.8 L), and the mixture was heated at 90° C. for 20 hr. The solvent was evaporated under reduced pressure, and sodium hydrogencarbonate was added to the residue under ice-cooling until the mixture assumed weak alkalinity. The mixture was extracted with chloroform, and the organic layer was dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure and diisopropyl ether was added to the residue. The mixture was heated and allowed to cool. The precipitated crystals were collected by filtration and dried by heating under reduced pressure to give 4-chloro-2-ethylimidazole-5-carbaldehyde (211.5 g) as brown crystals.

1. customThe solvent was evaporated under reduced pressure, and sodium hydrogencarbonate
2. additionwas added to the residue under ice-
3. temperaturecooling until the mixture
4. extractionThe mixture was extracted with chloroform
5. dry with materialthe organic layer was dried over anhydrous magnesium sulfate
6. customThe solvent was evaporated under reduced pressure and diisopropyl ether
7. additionwas added to the residue
8. temperatureThe mixture was heated
9. temperatureto cool
10. filtrationThe precipitated crystals were collected by filtration
11. customdried
12. temperatureby heating under reduced pressure