Hydrochloric Acid → 5-Formylpyridine-2-carbonitrile

Participants

Reaction Steps

The 73:27 mixture (933 mg, 5.15 mmol) of 1-methyl-5-(1,3-dioxolan-2-yl)-2(1H)-pyridone and 1-methyl-3-(1,3-dioxolan-2-yl)-2(1H)-pyridone was dissolved in tetrahydrofuran (10.0 mL). To this, 1N hydrochloric acid (10.0 mL) was added under a nitrogen atmosphere at room temperature and the mixture was stirred at the same temperature for 12 hours. Then, the reaction mixture was neutralized with a saturated aqueous sodium bicarbonate solution, and extraction with ethyl acetate was performed, followed by washing with brine and drying over anhydrous sodium sulfate. The solvent was evaporated off under reduced pressure, and thereby 6-cyano-3-pyridinecarboxaldehyde (364 mg, yield: 100%) was obtained. The residue was purified by preparative thin-layer chromatography (ethyl acetate) to give 1-methyl-5-formyl-2(1H)-pyridone (309 mg, yield: 45%).

Provenance & Evidence