Isoamyl Nitrite → 3-Fluoro-2-nitropyridine

온도

0 °C

To a stirred solution of 3-Amino 2-nitro pyridine (2.5 g, 17.97 mmol) in dry ethanol (20 ml) was added 10 ml of tetrafluoroboric acid (48% in water). The reaction mixture was cooled to 0° C. and isoamyl nitrite (2.6 g, 22.4 mmol) was added dropwise at 0° C. and stirred at 0° C. for 1 hour. The reaction mixture was filtered, and the solid obtained was washed with diethyl ether. The filtered solid was added to preheated (150 mL) toluene with stirring and reaction mixture was refluxed for 24 hours. The solvent was evaporated and the residue taken in ethyl acetate (200 ml) and washed with water followed by brine, dried over anhydrous sodium sulfate and concentrated under reduced pressure to get the crude 3-fluoro-2-nitropyridine. This was purified by column over silica gel using 10% ethyl acetate in pet ether as eluant to get 1 g (39%) of the title compound as a yellow solid.