Ethyl Acetate → 7-Bromo-2-ethyl-3-nitropyrazolo[1,5-a]pyridine

Participants

Reaction Steps

To a solution of 7-bromo-2-ethylpyrazolo[1,5-a]pyridine (1.1 g) dissolved in acetonitrile (20 mL) was added nitronium tetrafluoroborate (1.3 g) was added thereto while cooling with ice, and the reaction mixture was stirred for 30 minutes. The reaction mixture was then added to ice water, extraction was performed with ethyl acetate, and the organic extract was washed with water and brine. The obtained organic extract was dried over anhydrous magnesium sulfate and filtered, and the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography and the title compound (670 mg) was obtained as yellow crystals from the n-hexane:ethyl acetate (10:1) fraction.

Provenance & Evidence