反应详情

To a solution of N-methylimidazole (5 g, 0.06 mol), acetonitrile (32 mL) and triethylamine (15 mL), cooled to −20° C. was added ethyl chloroformate (13 mL, 0.137 mol), and the mixture allowed to slowly warm to room temperature and stirred for 3.5 hr. The solution was filtered (triethylamine hydrochloride) and concentrated under vacuum. The residue was purified by distillation under reduced pressure (0 Torr, 102° C.) to yield the product as a white solid. Yield (6.26 g, 68%) 1H NMR (DMSO): δ 7.44 (d, 1H, J=2.8 Hz), 7.04 (d, 1H, J=2.8 Hz), 4.26 (q, 2H, J=3.5 Hz), 3.91 (s, 3H), 1.26 (t, 3 h, J=3.5 Hz). 13C (DMSO): 159.3, 129.1, 127.7, 61.0, 36.0, 14.5.

1. filtrationThe solution was filtered (triethylamine hydrochloride)
2. concentrationconcentrated under vacuum
3. distillationThe residue was purified by distillation under reduced pressure (0 Torr, 102° C.)