反应详情

Lithium aluminum hydride (1.1 g, 30 mmol) is suspended in THF (50 ml), and thereto is added with stirring 3-(3,5-dimethoxypyridin-4-yl)propionic acid ethyl ester (3.5 g, 15 mmol) obtained in Reference Example 22 at 50° C. over a period of time for 40 minutes. The mixture is further heated under reflux for 30 minutes, and thereto are added successively water (1.1 ml), a 15% aqueous sodium hydroxide solution (1.1 ml) and water (3.3 ml) in order to quench the reaction. The reaction solution is filtered, and the insoluble materials are removed, and the filtrate is concentrated under reduced pressure. The residue is purified by silica gel column chromatography (eluent: chloroform/methanol), and further recrystallized from isopropyl ether/hexane to give the title compound (2.9 g) as colorless crystals, m.p. 88-89° C.

1. customobtained in Reference Example 22 at 50° C. over a period of time for 40 minutes
2. temperatureThe mixture is further heated
3. temperatureunder reflux for 30 minutes
4. customa 15% aqueous sodium hydroxide solution (1.1 ml) and water (3.3 ml) in order to quench
5. customthe reaction
6. filtrationThe reaction solution is filtered
7. customthe insoluble materials are removed
8. concentrationthe filtrate is concentrated under reduced pressure
9. customThe residue is purified by silica gel column chromatography (eluent: chloroform/methanol)
10. customfurther recrystallized from isopropyl ether/hexane