反应详情

A solution (2.3 l) of 3-[2-(3,4-diethoxyphenyl)thiazole-4-yl]propionic acid (254.5 g) in methanol was ice-cooled, and 58 ml of thionyl chloride was added dropwise. After completion of the addition, the resulting mixture was heated under reflux for 2 hours and cooled to room temperature. The solvent was distilled off under reduced pressure, and the residue was subjected to extraction with ethyl acetate. The organic layer was washed with a saturated aqueous sodium hydrogencarbonate solution, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-hexane=1/3). The solvent was distilled off under reduced pressure, and the residue was recrystallized from an ethyl acetate/n-hexane mixed solvent, to thereby obtain 219.35 g (yield: 68%) of methyl 3-[2-(3,4-diethoxyphenyl)thiazole-4-yl]propionate as a white powder.

1. temperaturecooled
2. additionAfter completion of the addition
3. temperaturethe resulting mixture was heated
4. temperatureunder reflux for 2 hours
5. distillationThe solvent was distilled off under reduced pressure
6. extractionthe residue was subjected to extraction with ethyl acetate
7. washThe organic layer was washed with a saturated aqueous sodium hydrogencarbonate solution
8. dry with materialdried over anhydrous sodium sulfate
9. distillationThe solvent was distilled off under reduced pressure
10. customthe residue was purified by silica gel column chromatography (eluent: ethyl acetate/n-hexane=1/3)
11. distillationThe solvent was distilled off under reduced pressure
12. customthe residue was recrystallized from an ethyl acetate/n-hexane mixed solvent