反应详情

温度

-78 °C

To a solution of 5-Bromo-4-chloro-2,6-dimethoxy-pyrimidine (0.546 g, 2.16 mmol) in THF (22 mL) at −78° C. was added n-butyllithium (1.6 M in hexanes, 1.48 mL, 2.37 mmol) over 2 min. Reaction mixture was stirred from 45 min at −78° C., then acetone (0.31 mL, 4.32 mmol) was added. Reaction mixture was stirred for 1 h at −78° C., then quenched with saturated ammonium chloride solution and extracted with ethyl acetate. Organic layer was washed with saturated ammonium chloride solution, dried (MgSO4), concentrated and purified by flash column chromatography (silica gel, 10 to 30% ethyl acetate/hexane) to give a colorless oil (0.275 g, 55%). 1H NMR (300 MHz, CDCl3): δ 3.97 (br s, 1H), 3.92 (s, 3H), 3.82 (s, 3H), 1.54 (s, 6H). Mass spectrum: 233.0, 235.0 (M+H)+.

1. customReaction mixture
2. customReaction mixture
3. stirringwas stirred for 1 h at −78° C.
4. customquenched with saturated ammonium chloride solution
5. extractionextracted with ethyl acetate
6. washOrganic layer was washed with saturated ammonium chloride solution
7. dry with materialdried (MgSO4)
8. concentrationconcentrated
9. custompurified by flash column chromatography (silica gel, 10 to 30% ethyl acetate/hexane)