126055-32-1

109-01-3

107-04-0

5753-26-4

1. 10 mL of 25% NaOH solution and 1 mL (9 mmol) of N-methylpiperazine were added sequentially to the reaction flask. 2. the mixture was heated to 50 °C and 1.8 mL (18 mmol) of 1-bromo-2-chloroethane was added slowly and dropwise. 3. The reaction mixture was kept at 50 °C with stirring for 6 hours and subsequently cooled to room temperature. 4. The reaction solution was extracted using ethyl acetate, the extract was washed with saturated brine solution, dried over anhydrous sodium sulfate and filtered. 5. The filtrate was concentrated to dryness under reduced pressure and a small amount of ethanol/NaOH solution was added dropwise to the residue. 6. The mixture was shaken and allowed to stand in a refrigerator and subsequently concentrated to dryness under reduced pressure to give 0.43 g of the white solid product 1-(2-chloroethyl)-4-methylpiperazine dihydrochloride in 23% yield. 7. The melting point of the product was determined to be 227-230 °C.