반응 #9286

반응 방정식

nitronium tetrafluoroborate

7-bromo-2-ethyl-4-methoxypyrazolo[1,5-a]pyridine

water

→

title compound

수율 47.9%

7-Bromo-2-ethyl-4-methoxy-3-nitropyrazolo[1,5-a]pyridine

수율 47.9%

용매

acetonitrile

반응 조건

후처리

1. 1
   workup.ADDITIONwas added
2. 2
   추출extraction
3. 3
   세척the extract was washed with saturated aqueous sodium hydrogencarbonate and brine
4. 4
   건조dried over magnesium sulfate
5. 5
   workup.DISTILLATIONthe solvent was distilled off under reduced pressure

실험 절차

After adding nitronium tetrafluoroborate (176 mg) to a solution of 7-bromo-2-ethyl-4-methoxypyrazolo[1,5-a]pyridine (282 mg) in acetonitrile (20 mL) at 0° C., the mixture was stirred for 20 minutes. Upon completion of the reaction, water was added, extraction was performed with ethyl acetate, the extract was washed with saturated aqueous sodium hydrogencarbonate and brine and dried over magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue was subjected to silica gel column chromatography (20 g), and the title compound (159 mg) was obtained from the n-hexane:ethyl acetate (3:1) fraction as yellow crystals.

출처