反应详情

To a solution of ethyl 2-methyl-1,3-thiazole-4-carboxylate (14.53 g) in MeCN (150 mL) was added NBS (22.66 g), followed by heating under reflux for 3 hours. To the reaction mixture was added NBS (7.55 g), followed by heating under reflux for 2 hours. Under ice-cooling, to the reaction mixture was added a saturated aqueous NaHCO3 solution, followed by stirring for 5 minutes, and then extraction with EtOAc. The organic layer was dried over MgSO4 and then concentrated under reduced pressure. The residue obtained was purified by silica gel column chromatography (hexane:EtOAc=from 100:0 to 60:40) to obtain ethyl 5-bromo-2-methyl-1,3-thiazole-4-carboxylate (8.52 g) as a yellow solid.

1. temperatureby heating
2. temperatureunder reflux for 3 hours
3. temperatureby heating
4. temperatureunder reflux for 2 hours
5. temperatureUnder ice-cooling, to the reaction mixture
6. extractionextraction with EtOAc
7. dry with materialThe organic layer was dried over MgSO4
8. concentrationconcentrated under reduced pressure
9. customThe residue obtained
10. customwas purified by silica gel column chromatography (hexane:EtOAc=from 100:0 to 60:40)