反应详情

温度

80 °C

To a suspension of ethyl 5-bromo-imidazo[1,2-a]pyridine-2-carboxylate (1.50 g, 5.6 mmol), Pd(PPh3)4 (322 mg, 0.279 mmol) in a mixture of toluene (17 mL), NaHCO3 1M (6 mL) and MeOH (4 mL) was added phenylboronic acid at room temperature. The resulting reaction mixture was heated at 80° C. for 12 h, cooled, and diluted with water (50 mL). The insoluble matter was filtered off, and the phases were separated. The aqueous phase was extracted with ethyl acetate, the combined organic layers were washed with water and the solvent was removed under reduced pressure. The crude product was purified by chromatography (prepacked 25 g silicagel column, DCM/MeOH from 100/0 to 99/1 as eluent) to afford 1.41 g of ethyl 5-phenyl-imidazo[1,2-a]pyridine-2-carboxylate (Yield: 95%) as a yellowish solid (M.P.: 123-123.8° C.)

1. customThe resulting reaction mixture
2. temperaturecooled
3. filtrationThe insoluble matter was filtered off
4. customthe phases were separated
5. extractionThe aqueous phase was extracted with ethyl acetate
6. washthe combined organic layers were washed with water
7. customthe solvent was removed under reduced pressure
8. customThe crude product was purified by chromatography (prepacked 25 g silicagel column, DCM/MeOH from 100/0 to 99/1 as eluent)