855636-38-3

4021-11-8

855636-38-3

2-Methyl-4-pyridinecarboxylic acid (5.0 g, 36.5 mmol) was used as raw material and mixed with selenium dioxide (10.1 g, 91.3 mmol) in 250 ml of dioxane. The reaction mixture was heated to 110°C and the reaction was continued under magnetic stirring for 24 hours. The reaction process was monitored by thin layer chromatography (TLC). Upon completion of the reaction, the reaction mixture was filtered while hot to remove insoluble impurities. Subsequently, the solvent was removed by distillation under reduced pressure to obtain the crude product. The crude product was purified by recrystallization from anhydrous ethanol and finally dried under vacuum to give 2-formyl-4-pyridinecarboxylic acid as a white solid in 72% yield and 98% purity.