1-Phenylpyrazol-5-ylamine → 5-Bromo-1-phenyl-1H-pyrazolo[3,4-b]pyridine

Participants

Reaction Steps

Dissolve 1-phenyl-5-aminopyrazole (Tokyo Kasei Kogyo Co. LTD; 1.5 g, 9.4 mmol) and 2-bromomalonaldehyde (Aldrich; 1.42 g, 9.4 mmol) in glacial acetic acid (170 mL) and reflux under nitrogen for 5 h. Concentrate under reduced pressure and purify via chromatography (silica gel, dichloromethane) to obtain 740 mg (28%) of the title compound as an off-white solid. TOF MS ES+ exact mass calculated for C12H9N3Br (p+H): m/z=273.9980, Found. 273.9965.

Provenance & Evidence