28544-83-4

610-96-8

107-15-3

28544-83-4

Methyl 2-chlorobenzoate (5.00 g, 29.0 mmol), ethylenediamine (8.81 g, 146.7 mmol) and anhydrous potassium carbonate (8.10 g, 58.6 mmol) were dissolved in N,N-dimethylformamide (DMF, 100 mL) under nitrogen protection. The reaction mixture was stirred at room temperature for the reaction. Upon completion of the reaction, the mixture was concentrated under reduced pressure to remove the DMF. water was added to the residue and extracted three times with ethyl acetate. The organic phases were combined, washed with saturated sodium chloride solution and dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated under reduced pressure to give a black residue. The residue was purified by silica gel column chromatography using gradient elution with ethyl acetate/petroleum ether (20-50%) to afford the white solid product 3,4-dihydro-1H-benzo[e][1,4]diazepan-5(2H)-one (2.5 g, 52.6% yield).