反应详情

温度

100 °C

A mixture of 2-bromo-5-fluoro-6-methylpyridine (25 g, 132 mmol), 1-ethoxyvinyltri-n-butyltin (48.9 ml, 145 mmol) and bis(triphenylphosphine)palladium (II) chloride (4.62 g, 6.58 mmol) in 1,4-dioxane (250 ml) was heated to 100° C. under nitrogen over night. The reaction was then cooled to room temperature and the solvent was removed in vacuo. The residue was purified by silica gel chromatography (eluted with a gradient of ethyl acetate in hexanes) to give the product 2-(1-ethoxy-ethenyl)-5-fluoro-6-methyl-pyridine, together with an unidentified impurity. This product was used in the next step. 1H NMR (500 MHz, CDCl3): δ 7.51 (dd, 1H), 7.28 (t, 1H), 5.33 (d, 1H), 4.31 (d, 1H), 3.96 (q, 2H), 2.53 (d, 3H), 1.43 (t, 3H).

1. temperatureThe reaction was then cooled to room temperature
2. customthe solvent was removed in vacuo
3. customThe residue was purified by silica gel chromatography (
4. washeluted with a gradient of ethyl acetate in hexanes)