反应详情

温度

20 °C

To a solution of 2,4-dibromopyridine (3.00 g, 12.66 mmol) in dry tetrahydrofuran (10 mL) under an atmosphere of argon was added tetrakis(triphenylphosphine)palladium(0) (0.435 g, 0.38 mmol). The reaction vessel was put in a water-bath (˜20° C.) and cyclopropylzinc(II) bromide, 0.5M in tetrahydrofuran (30.1 mL, 15.05 mmol) was added is over a period of 10 minutes. The reaction mixture was stirred at 20° C. for 80 minutes. More cyclopropylzinc(II) bromide, 0.5M in tetrahydrofuran (7.52 mL, 3.76 mmol) was added and the reaction mixture was stirred for another 40 minutes before it was poured into saturated aqueous NaHCO3 (100 mL) and diluted with EtOAc (100 mL). The layers were separated and the aqueous layer extracted with EtOAc (50 mL). The organics were combined, dried (Na2SO4), filtered and the solvent was evaporated at reduced pressure. The crude was purified by flash chromatography on silica gel to afford 2.12 g (85%) of the title compound.

1. customThe reaction vessel was put in a water-bath
2. stirringthe reaction mixture was stirred for another 40 minutes before it
3. customThe layers were separated
4. extractionthe aqueous layer extracted with EtOAc (50 mL)
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. customthe solvent was evaporated at reduced pressure
8. customThe crude was purified by flash chromatography on silica gel