Hydrochloric Acid → 1-(4-Nitrophenyl)piperazine

Participants

Reaction Steps

A solution of 1-chloro-4-nitrobenzene (15 g, 94.5 mmol) in 1-butanol (75 mL) was added over 20-30 minutes to a refluxing solution of anhydrous piperazine (24.4 g, 284 mmol) in 1-butanol (75 mL) and the mixture maintained at reflux overnight. The solvent was removed under reduced pressure to afford a solid, to which was added 2N hydrochloric acid (400 mL). The aqueous layer was washed twice with ethyl acetate, cooled to below 10° C. and basified with a cold solution of 40% sodium hydroxide to pH 10, keeping temperature below 20° C. The mixture was extracted with ethyl acetate (4×200 mL) then the combined organic layers were washed with brine and dried over sodium sulfate. Filtration and concentration under reduced pressure afforded 1-(4-nitro-phenyl)-piperazine (13.7 g, 70%) as a yellow solid.

Provenance & Evidence