反应详情

In a flame dried round-bottomed flask equipped with a magnetic stir bar and under inert atmosphere (N2), a suspension of 2,4-dibromo-pyridine (1.90 g, 8.02 mmol) in dry Et2O (40 mL) was treated with n-BuLi (3.36 mL of a 2.5M solution in hexanes, 8.42 mmol) at −78° C. The reaction mixture was stirred at this temperature for 30 min. N,N-Dimethyl-formamide (0.78 mL, 10.03 mmol) was then added and the mixture allowed to warm to rt over a period of 1 h and stirred at this temperature for 20 min. The reaction was quenched by the addition of sat. aq. NH4Cl (30 mL). The layers were separated and the aq. layer extracted with Et2O (3×50 mL). The combined org. extracts were dried over Na2SO4, filtered, and the solvent removed under reduced pressure. Purification of the residue by FC (10:1 to 2:1 hept-EA) gave the title compound as a white solid. TLC:rf (1:1 hept-EA)=0.44.

1. stirringstirred at this temperature for 20 min
2. customThe reaction was quenched by the addition of sat. aq. NH4Cl (30 mL)
3. customThe layers were separated
4. extractionthe aq. layer extracted with Et2O (3×50 mL)
5. dry with materialextracts were dried over Na2SO4
6. filtrationfiltered
7. customthe solvent removed under reduced pressure
8. customPurification of the residue by FC (10:1 to 2:1 hept-EA)