Cesium carbonate → 2-Nitro-5-(3-nitrophenoxy)pyridine

To a solution of 5-bromo-2-nitropyridine (20.5 g, 101 mmol) and cesium carbonate (50 g, 153 mmol) in N,N-dimethylformamide (200 mL) was added dropwise a solution of 3-nitrophenol (15.5 g, 111 mmol) in N,N-dimethylformamide (100 mL) for 1 hr, and the mixture was stirred at room temperature for 12 hr. The reaction mixture was concentrated under reduced pressure, and the obtained residue was diluted with water (300 mL) and extracted with ethyl acetate (600 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 (14.28 g, 54%) as colorless crystals.

1. concentrationThe reaction mixture was concentrated under reduced pressure
2. additionthe obtained residue was diluted with water (300 mL)
3. extractionextracted with ethyl acetate (600 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

ORD-Eintrag

ord-5a672481cc514cb989b1928ff2d224fc

Quelldatensatz

uspto-grants-2013_01

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08344135B2