Synthesis
Ethyl acetoacetate (0.97 mL, 7.7 mmol) and pyrrolidine (0.63 mL, 7.6 mmol) were dissolved in toluene (20 mL) and the mixture was transferred to a round-bottomed flask fitted with a Dean-Stark water separator. The reaction mixture was heated to reflux for 1 h under nitrogen protection. Upon completion of the reaction, the solvent was removed by distillation under reduced pressure to afford ethyl 3-(1-pyrrolidinyl)crotonate (1.3 g, 94.8% yield), and the resulting product could be used in subsequent reactions without further purification.
References
[1] Organic Letters, 2018, vol. 20, # 4, p. 999 - 1002
[2] Bioorganic and Medicinal Chemistry Letters, 2018, vol. 28, # 17, p. 2879 - 2884
[3] Angewandte Chemie - International Edition, 2014, vol. 53, # 17, p. 4377 - 4381
[4] Angew. Chem., 2014, vol. 126, # 17, p. 4466 - 4470,5
[5] Canadian Journal of Chemistry, 1985, vol. 63, p. 1874 - 1883
