反应详情

温度

0 °C

A solution of 6,7-dimethoxy-4-(3,4-dimethoxyphenyl)-3-ethoxycarbonylquinoline-2-acetic acid ethyl ester (5.8 g) in tetrahydrofuran (100 ml) was added drop by drop at 0° C. to a suspension of lithium aluminum hydride (0.455 g) in tetrahydrofuran (50 ml). After the reaction mixture was stirred at 0° C. for 1 hour, water (2.5 ml) was added drop by drop, followed by stirring for 30 more minutes. After the insoluble solid was filtered off, the filtrate was concentrated under reduced pressure. The residue was subjected to silica gel column chromatography and eluted with chloroform-ethyl acetate (1:1, v/v) to yield 6,7-dimethoxy-4-(3,4-dimethoxyphenyl)-2-(2-hydroxyethyl)quinoline-3-carboxylic acid ethyl ester (1.75 g, 33%), which was then recrystallized from ethyl acetate-hexane to yield a colorless prismatic crystal having a melting point of 150° to 151° C.

1. stirringby stirring for 30 more minutes
2. filtrationAfter the insoluble solid was filtered off
3. concentrationthe filtrate was concentrated under reduced pressure
4. washeluted with chloroform-ethyl acetate (1:1