N-bromobutanimide → 3-bromo-6-(1-tert-butyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-ol

Participants

Reaction Steps

To a solution of 6-(1-tert-butyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-ol (138 mg, 0.538 mmol) in acetonitrile (6 mL) was added N-bromosuccinimide (105 mg, 0.590 mmol). The solution was stirred at room temperature for 1 h. The reaction was diluted with dichloromethane, washed with water and 2N NaOH. The combined aqueous layers were neutralized and extracted with ethyl acetate. The combined organic layers were washed with brine, dried, filtered and concentrated under reduced pressure. The residue was purified by flash column chromatography on silica gel to afford 3-bromo-6-(1-tert-butyl-1H-pyrazol-4-yl)pyrazolo[1,5-a]pyridin-4-ol.

Provenance & Evidence