反应详情

温度

140 °C

3-Benzyloxy-2-bromopyridine (8 g, 30 mmol) and ethyl 3-hydroxybenzoate (13.3 g, 80 mmol) are dissolved in DMF (50 ml), and thereto are added potassium carbonate (28 g, 0.2 mol) and cuprous bromide (11.5 g, 80 mmol). The mixture is heated under reflux at 140° C. for one hour. After being allowed to cool, the reaction solution is acidified with a 15% aqueous hydrochloric acid solution (50 ml), and then neutralized with a saturated aqueous sodium hydrogen carbonate solution, and extracted with ethyl acetate (300 ml×2). The organic layer is washed with a saturated brine (200 ml×2), dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue is purified by silica gel column chromatography (eluent: ethyl acetate/hexane) to give 3-benzyloxy-2-(3-ethoxycarbonyl-phenoxy)pyridine as a pale yellow oil.

1. temperatureThe mixture is heated
2. temperatureto cool
3. extractionextracted with ethyl acetate (300 ml×2)
4. washThe organic layer is washed with a saturated brine (200 ml×2)
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue is purified by silica gel column chromatography (eluent: ethyl acetate/hexane)