反应详情

Under a nitrogen stream, sulfuric acid (8 mL) was added dropwise over 3 hours to a solution of naphthalene-1,4-dicarboxylic acid (1.107 g, 5.12 mmol) in 2-propanol (60 mL) while heating to reflux. The resultant solution was cooled to room temperature and then saturated aqueous sodium carbonate was added thereto. The mixture was then stirred for 10 minutes at room temperature. The resultant mixture was twice extracted with dichloromethane. After drying the organic layer over anhydrous magnesium sulfate, solvent was removed by distillation under reduced pressure. The resulting residue was purified by silica gel column chromatography (developing solution=ethyl acetate:n-hexane (15:85)), to thereby obtain the titled compound (588 mg, 38%).

1. temperaturewhile heating to reflux
2. extractionThe resultant mixture was twice extracted with dichloromethane
3. dry with materialAfter drying the organic layer over anhydrous magnesium sulfate, solvent
4. customwas removed by distillation under reduced pressure
5. customThe resulting residue was purified by silica gel column chromatography (developing solution=ethyl acetate:n-hexane (15:85))