反应详情

A 1000-mL round-bottom flask was charged with 8-chloro-5-methoxy-2-methylquinoline hydrochloride (50.0 g, 204.8 mmol), methanol (300 mL), aqueous sodium hydroxide solution (3 M, 205 mL), and 10% palladium on active carbon (25 g). The system was purged with hydrogen gas, and the resulting mixture was stirred under a hydrogen atmosphere for 3 h at room temperature. The reaction mixture was filtered through a pad of Celite and concentrated under vacuum to remove most of methanol. The resulting solution was extracted with ethyl acetate (2×2000 mL). The organic layers were combined, dried over anhydrous sodium sulfate, filtered, and concentrated under vacuum. The residue was purified via column chromatography on silica gel (gradient elution with 0-20% ethyl acetate/petroleum ether) to afford 5-methoxy-2-methylquinoline (36 g, 63%) as a yellow solid. MS (ES, m/z): 174 [M+H]+

1. customThe system was purged with hydrogen gas
2. filtrationThe reaction mixture was filtered through a pad of Celite
3. concentrationconcentrated under vacuum
4. customto remove most of methanol
5. extractionThe resulting solution was extracted with ethyl acetate (2×2000 mL)
6. dry with materialdried over anhydrous sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated under vacuum
9. customThe residue was purified via column chromatography on silica gel (gradient elution with 0-20% ethyl acetate/petroleum ether)