Synthesis of ethyl 1-methyl-1H-imidazole-2-carboxylate: triethylamine (3.40 mL, 24.4 mmol) and ethyl chloroformate (2.34 mL, 24.4 mmol) were added drop-wise to a solution of 1-methyl-1H-imidazole (1.00 g, 12.2 mmol) in acetonitrile (4.0 mL) at 0 °C. The reaction mixture was stirred at room temperature for 16 hours. After completion of the reaction, the mixture was filtered through diatomaceous earth and the filtrate was concentrated under reduced pressure to remove the solvent. The resulting crude product was purified by fast column chromatography (silica gel as stationary phase and hexane/ethyl acetate as eluent) to afford ethyl 1-methyl-1H-imidazole-2-carboxylate (1.50 g, 9.73 mmol, 80% yield) as a white solid. The structure of the product was confirmed by 1H-NMR (400 MHz, CDCl3) and ESI-MS: 1H-NMR δ 1.42 (3H, t, J = 7.2 Hz), 4.01 (3H, s), 4.40 (2H, q, J = 7.2 Hz), 7.01-7.03 (1H, m), 7.13-7.15 (1H, m); ESI-MS m /z = 155 (M + H)+.
