Piperazine → 1-(4-Nitro-2-pyridinyl)piperazine

Participants

Reaction Steps

A solution of 2-chloro-4-nitropyridine (4.89 g), and piperazine (7.90 g) in pyridine (90 ml) was heated under reflux for 5 hours and then evaporated. The residue was dissolved in water and the solution was basified with sodium bicarbonate (to pH 8-9) and then continuously extracted with dichloromethane. The extract was dried (Na2SO4) and evaporated to give an oil which was chromatographed on silica gel. Elution with dichloromethane/methanol/concentrated aqueous ammonia (98:2:1) first gave a solid that was crystallised from ethyl acetate/hexane to give 1-[4-nitro-2-pyridinyl]piperazine (1.21 g), m.p. 92°-93° C.

Provenance & Evidence