Reaction #696713

Reaction equation

N-methylimidazole

acetonitrile

Ethyl chloroformate

→

solid

Yield 82.0%

Ethyl 1-methylimidazole-2-carboxylate

Yield 82.0%

Solvents

triethylamine

Conditions

Workup

1. 1
   Otherequipped with a mechanical stirrer
2. 2
   Otherthe temperature between -20° C. and -25° C
3. 3
   Temperatureto slowly warm to room temperature
4. 4
   workup.STIRRINGstir for 36 h
5. 5
   OtherPrecipitated triethylamine hydrochloride was removed by filtration
6. 6
   Concentrationthe solution concentrated in vacuo at 65° C
7. 7
   workup.DISTILLATIONThe resulting oil was purified by distillation under reduced pressure (2 torr, 102° C.)

Procedure

N-methylimidazole (320 g, 3.9 mol) was combined with 2 L acetonitrile and 1 L triethylamine in a 12 L flask equipped with a mechanical stirrer and the solution cooled to -20° C. Ethyl chloroformate (1000 g, 9.2 mol) was added with stirring, keeping the temperature between -20° C. and -25° C. The reaction was allowed to slowly warm to room temperature and stir for 36 h. Precipitated triethylamine hydrochloride was removed by filtration and the solution concentrated in vacuo at 65° C. The resulting oil was purified by distillation under reduced pressure (2 torr, 102° C.) to provide a white solid (360 g, 82% yield).

Source