反应详情

A solution of 1-(6-bromopyridin-2-yl)ethanone (9.2 g, 46.0 mmol) in acetic acid (25 mL) was heated to 70° C. and bromine (2.4 mL, 46.0 mmol) was added dropwise over 30 minutes. After 75 minutes, the solution was cooled to room temperature and a yellow solid precipitated which was collected by filtration and washed with acetic acid (3×10 mL) The solid was then dissolved in a mixture of ethyl acetate (150 mL), hexanes (50 mL), and saturated aqueous sodium bicarbonate (75 mL). The layers were separated and the organic layer was washed with brine (30 mL), dried over sodium sulfate, filtered, and concentrated. The crude residue was purified by silica gel chromatography (10-50% dichloromethane/hexanes) to give the title compound as a white solid.

1. customa yellow solid precipitated which
2. filtrationwas collected by filtration
3. washwashed with acetic acid (3×10 mL) The solid
4. dissolutionwas then dissolved in a mixture of ethyl acetate (150 mL), hexanes (50 mL), and saturated aqueous sodium bicarbonate (75 mL)
5. customThe layers were separated
6. washthe organic layer was washed with brine (30 mL)
7. dry with materialdried over sodium sulfate
8. filtrationfiltered
9. concentrationconcentrated
10. customThe crude residue was purified by silica gel chromatography (10-50% dichloromethane/hexanes)