反应详情

温度

60 °C

To the solution of ethyl 3-bromo-5-chloropyridine-4-carboxylate (28 g, 105 mmol) in dioxane (300 mL) in a 1 L round bottom flask was added dimethylzinc (105 mL, 1.0 M in hexane) and (1,1′-bis(diphenylphosphino)ferrocene)dichloropalladium (II) dichloromethane complex (1.3 g, 1.6 mmol). The resulting mixture was heated at 60° C. for 20 hours. After cooling, the reaction mixture was poured into cold water (500 mL) and extracted with dichloromethane (3×200 mL). After evaporation of the solvent, the crude product was filtered through a silica pad (10 cm) with 20% ethyl acetate in hexane (400 mL), and the solvent was evaporated. The oily ethyl 3-chloro-5-methylpyridine-4-carboxylate (20 g, 90% yield) was used in the next step without further purification.

1. temperatureAfter cooling
2. extractionextracted with dichloromethane (3×200 mL)
3. customAfter evaporation of the solvent
4. filtrationthe crude product was filtered through a silica pad (10 cm) with 20% ethyl acetate in hexane (400 mL)
5. customthe solvent was evaporated