[1,2,4]Triazolo[1,5-a]pyridine-2-carbaldehyde

265643-91-2

1373338-09-0

[1,2,4]Triazolo[1,5-a]pyridin-2-ylmethanol (0.35 g, 2.3 mmol) was used as the raw material, which was dissolved in ethanol (50 mL), and manganese dioxide (IV) (1.02 g, 11.5 mmol) was added. The reaction mixture was heated to reflux for 2 days. After completion of the reaction, it was cooled to room temperature and the solids were removed by diatomaceous earth filtration. The filtrate was concentrated and the resulting residue was purified by reversed-phase column chromatography (eluent: 10% v/v aqueous acetonitrile containing 0.01% NH3-H2O) to afford [1,2,4]triazolo[1,5-a]pyridine-2-carboxaldehyde (0.15 g, 43% yield) as a white solid.ESI MS: m/z 148 [M + H]+.