Synthesis
General method: Benzyl chloroformate (1 mmol) was slowly added dropwise to a solution of n-butylamine (1 mmol), followed by placing the reaction mixture in a microwave reactor and irradiating it at 100 W power for appropriate times (see Tables 2, 3, 4 and 5 for specific times). The reaction process was monitored by thin layer chromatography (TLC) using dichloromethane: methanol (98:2) as the unfolding agent. Upon completion of the reaction, n-hexane (15-20 mL) was added to the mixture and allowed to stand overnight at room temperature. The solid product formed was collected by filtration, washed with hexane and dried to give benzyl butylcarbamate in good to excellent yield. Hydrogen chloride gas was generated during the reaction, a phenomenon that confirmed that the protection of the amine group had been successfully carried out.
References
[1] Tetrahedron Letters, 2007, vol. 48, # 1, p. 55 - 59
[2] Tetrahedron Letters, 2007, vol. 48, # 46, p. 8170 - 8173
[3] Journal of the Korean Chemical Society, 2017, vol. 61, # 4, p. 151 - 156
[4] Chinese Chemical Letters, 2012, vol. 23, # 7, p. 789 - 792
[5] Tetrahedron Letters, 2008, vol. 49, # 32, p. 4799 - 4803
