Acetic anhydride (3) (1.2 equiv) was added to a solution of benzylamine (1) (1.0 equiv) and triethylamine (1.2 equiv) in EtOAc (0.50 M) at ambient conditions. After the solution was stirred at the same temperature for 30 min, the resultant mixture was poured into a solution of EtOAc and 1 M HCl aq. at the same temperature. The organic layer was washed with 1 M HCl aq., sat. NaHCO3 aq., brine, dried over MgSO4, filtered and concentrated in vacuo at room temperature.