反应详情

To a solution of 5-bromo-2-nitropyridine (20.0 g, 98.5 mmol) and cesium carbonate (48.1 g, 147 mmol) in N,N-dimethylformamide (150 mL) was added a solution of tert-butyl (3-hydroxyphenyl)carbamate (21.6 g, 103 mmol) in N,N-dimethylformamide (100 mL), and the mixture was stirred at room temperature for 2 days. The reaction mixture was concentrated under reduced pressure, the obtained residue was diluted with water (300 mL), and extracted with ethyl acetate (500 mL). The organic layer was washed with 5% aqueous sodium hydrogen carbonate solution (300 mL) and saturated brine (300 mL), and dried over anhydrous sodium sulfate. The insoluble material was filtered off, and the filtrate was concentrated under reduced pressure. The obtained residue was purified by basic silica gel column chromatography (hexane/ethyl acetate=90/10→60/40), and fractions containing the object product was concentrated under reduced pressure to give the title compound (19.4 g, 59%) as a pale-yellow oil.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. additionthe obtained residue was diluted with water (300 mL)
3. extractionextracted with ethyl acetate (500 mL)
4. washThe organic layer was washed with 5% aqueous sodium hydrogen carbonate solution (300 mL) and saturated brine (300 mL)
5. dry with materialdried over anhydrous sodium sulfate
6. filtrationThe insoluble material was filtered off
7. concentrationthe filtrate was concentrated under reduced pressure
8. customThe obtained residue was purified by basic silica gel column chromatography (hexane/ethyl acetate=90/10→60/40), and fractions
9. additioncontaining the object product
10. concentrationwas concentrated under reduced pressure