1-(4-Nitrophenyl)piperazine

110-85-0

100-00-5

6269-89-2

A solution of 1-chloro-4-nitrobenzene (650 g, 4.140 mol) in diethylene glycol dimethyl ether (1 L) was slowly added dropwise to a solution of piperazine (2.84 Kg, 33.12 mol) in diethylene glycol dimethyl ether (500 mL) at 100 °C. The reaction mixture was stirred continuously at 100°C for 6 hours. Upon completion of the reaction, the mixture was cooled to 40-45 °C and water (5 L) was slowly added to quench the reaction. Subsequently, the mixture was warmed to room temperature and stirring was continued for 1 hour. The precipitated solid was collected by filtration, washed sequentially with water (1 L) and petroleum ether (500 mL), and dried to give 700 g (81% yield) of 4-nitrophenylpiperazine as a yellow solid. [TLC detection conditions: ethyl acetate:petroleum ether (3:7); Rf value: 0.70].