反应详情

Ethyl 5-chloro-2-methylbenzoate (16.60 g, 83.56 mmol) and diethyl-(3-pyridyl)borane (13.52 g, 91.92 mmol) were dissolved in 100 mL tetrahydrofuran in a 500 mL round bottom flask equipped with a magnetic stirrer. Sodium carbonate (26.57 g, 250.69 mmol) and 50 mL water were added followed by palladium acetate (0.38 g, 1.67 mmol) and (2′-dicyclohexylphosphanyl-biphenyl-2-yl)-dimethyl-amine (AmPhos, 0.92 g, 2.51 mmol) and 25 mL ethanol. The mixture was heated at reflux for 6 h then cooled to ambient temperature. The mixture was diluted with 600 mL water and extracted with diethyl ether (2×300 mL). The organic phases were combined and extracted with 1N HCl (3×200 mL). The acidic extractions were combined and made basic with 5N aqueous sodium hydroxide. This basic layer was extracted with diethyl ether (3×500 mL) and the extracts were combined and dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to yield 19.57 g (97%) of ethyl 5-(3-pyridyl)-2-methylbenzoate as a brown oil.

1. customequipped with a magnetic stirrer
2. temperatureThe mixture was heated
3. temperatureat reflux for 6 h
4. extractionextracted with diethyl ether (2×300 mL)
5. extractionextracted with 1N HCl (3×200 mL)
6. extractionThe acidic extractions
7. extractionThis basic layer was extracted with diethyl ether (3×500 mL)
8. dry with materialdried over anhydrous sodium sulfate
9. filtrationfiltered
10. concentrationconcentrated under reduced pressure