反应详情

温度

90 °C

Lithium bromide (3.2 g, 37 mmol) and acetyl bromide (1.3 mL, 17 mmol) were added to a solution of (2-chloro-pyridin-5-yl)acetic acid ethyl ester (1.08 g, 5.42 mmol) in acetonitrile (7.2 mL), and the mixture was heated under reflux at an external temperature of 86 to 94° C. for 31 hours. The reaction mixture was dissolved in water. The solution was neutralized with a sodium hydroxide aqueous solution, followed by extraction with diethyl ether. The organic layer was dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The residue was purified by silica gel chromatography (hexane/ethyl acetate=4/1) to give the title compound (655 mg, 53%).

1. temperaturethe mixture was heated
2. extractionfollowed by extraction with diethyl ether
3. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
4. concentrationconcentrated under reduced pressure
5. customThe residue was purified by silica gel chromatography (hexane/ethyl acetate=4/1)