反应详情

A solution of 4-pentynoic acid (519 mg, 5.29 mmol) and Et3N (737 μL, 5.29 mmol) in DCM (10 mL) was treated with ethyl chloroformate (504 μL, 5.29 mmol) at rt for 15 min. Then N-methyl-piperazine (588 μL, 5.29 mmol) was added, and stirring was prolonged for 45 min. Work-up (sat. aq. NaHCO3) and concentration gave the title compound as a colorless oil. 1H NMR (CDCl3) δ 3.63 (t, 2H), 3.48 (t, 2H), 2.55 (m, 4H), 2.38 (quint., 4H), 2.30 (s, 3H).

1. concentration(sat. aq. NaHCO3) and concentration