反应详情

A mixture of methyl 2-hydroxy-3-(3-(pyridin-4-yl)benzamido)benzoate (0.9 g, 5 mmol) of propionic acid (50 mL) was stirred at reflux for 3 days. Then the mixture was adjusted to pH=7 by sodium bicarbonate. The mixture was extracted with ethyl acetate. The organic phase was washed with saturated sodium bicarbonate, brine, dried with anhydrous sodium sulfate. The solvent was removed under reduced pressure. The crude products was purified by chromatography (petroleum ether/ethyl acetate=5:1). 240 mg of methyl 2-(3-(pyridin-4-yl)phenyl)benzo[d]oxazole-7-carboxylate as a solid was obtained. Yield 28%. LC-MS (ESI) m/z: 331 (M+1)+.

1. temperatureat reflux for 3 days
2. extractionThe mixture was extracted with ethyl acetate
3. washThe organic phase was washed with saturated sodium bicarbonate, brine
4. dry with materialdried with anhydrous sodium sulfate
5. customThe solvent was removed under reduced pressure
6. customThe crude products was purified by chromatography (petroleum ether/ethyl acetate=5:1)