Ethyl N-piperazinecarboxylate

110-85-0

541-41-3

120-43-4

Piperazine (2 g, 23.2 mmol) and deionized water (10 mL) were added to a reaction flask and stirred at 25 °C until completely dissolved, then cooled to 0 °C. A methanol solution (20 mL) of ethyl chloroformate (1.26 g, 11.6 mmol) was slowly added dropwise with stirring. After the dropwise addition was completed, the reaction system was warmed to 25 °C and stirring was continued for 4 hours. Upon completion of the reaction, saturated aqueous sodium chloride solution (30 mL) and dichloromethane (200 mL) were added to the reaction solution for extraction and separation. The organic layer was collected and dried with anhydrous sodium sulfate. The organic solvent was removed by distillation under reduced pressure, and the resulting crude product was purified by column chromatography (eluent: dichloromethane/methanol, 40:1, v/v/v/v) to give ethyl N-piperazinecarboxylate (0.62 g, 33.7% yield) as a white solid.