反应详情

2,5-Dimethyl-3-furancarboxylic acid ethyl ester (14.6 g) (synthesized in accordance with the method described in J.A.C.S., 59, 2525 (1937)) was dissolved in ethanol (100 15 ml), and 1N aqueous sodium hydroxide (100 ml) was added. The mixture was stirred at room temperature for 1 hour, and then stirred under reflux for 30 minutes. The mixture was concentrated under reduced pressure, and the residue was dissolved in water and washed with diethyl ether. The aqueous layer was acidified with 1N hydrochloric acid and extracted with ethyl acetate. The extract was washed with water and saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate and concentrated under reduced pressure. precipitated crystals were recrystallized from acetone-hexane to give 2,5-dimethyl-3-furancarboxylic acid (7.3 g) as crystals.

1. stirringstirred
2. temperatureunder reflux for 30 minutes
3. concentrationThe mixture was concentrated under reduced pressure
4. dissolutionthe residue was dissolved in water
5. washwashed with diethyl ether
6. extractionextracted with ethyl acetate
7. washThe extract was washed with water and saturated aqueous sodium chloride
8. dry with materialdried over anhydrous magnesium sulfate
9. concentrationconcentrated under reduced pressure
10. customprecipitated crystals
11. customwere recrystallized from acetone-hexane