反应详情

温度

110 °C

To a solution of 2-bromo-5-fluoro-3-nitropyridine (20 g, 90.50 mmol) in 1, 4 dioxane (270 mL) was added tributyl vinyl tin (34.54 g, 108.60 mmol). The reaction mixture was degassed using nitrogen for 30 min. Bis-(triphenylphosphin)-palladium(II)-chloride (3.17 g, 4.5 mmol) was added to the reaction mixture. Reaction mass was stirred at 110° C. for 16 h. The reaction mixture was cooled to 25° C. Water was added to the reaction mass and extracted with EtOAc. Organic layer was washed with brine and dried over Na2SO4. The organic layer was concentrated in vacuo and purified by column chromatography on silica gel using 0-2% EtOAc in hexane to give 5-fluoro-3-nitro-2-vinylpyridine: 1H NMR (400 MHz, DMSO-d6): δ 5.742 (dd, 1H, J=2 Hz, 10.8 Hz), 6.45 (dd, 1H, J=2 Hz, J=16.8 Hz), 7.11-7.17 (m, 1H), 8.489-8.516 (m, 1H), 8.959 (d, 1H, J=2.4 Hz).

1. customThe reaction mixture was degassed
2. customfor 30 min
3. customReaction mass
4. temperatureThe reaction mixture was cooled to 25° C
5. extractionextracted with EtOAc
6. washOrganic layer was washed with brine
7. dry with materialdried over Na2SO4
8. concentrationThe organic layer was concentrated in vacuo
9. custompurified by column chromatography on silica gel using 0-2% EtOAc in hexane