Methyl p-toluenesulfonate → 1,2-dimethyl-1H-imidazole-5-carbaldehyde

Participants

Reaction Steps

In DMF (10 mL) was dissolved 2-methyl-1H-imidazole-5-carbaldehyde (1.00 g, 9.08 mmol). Potassium carbonate (2.51 g, 18.2 mmol) and methyl p-toluenesulfonate (2.06 mL, 13.6 mmol) were added under ice-cooling and the mixture was stirred at room temperature for 6 hours. A 1 mol/L aqueous sodium hydroxide solution and water were added to the reaction mixture. Extraction with ethyl acetate, washing with a 1 mol/L aqueous sodium hydroxide solution and drying over anhydrous magnesium sulfate were performed. After filtration, the solvent in the filtrate was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform/methanol=19/1) to give 1,2-dimethyl-1H-imidazole-5-carbaldehyde (180 mg, 16% yield).

Provenance & Evidence