4-Nitrophenol-piperazine (2/1)

In the title adduct, C6H5NO3 center dot 0.5C(4)H(10)N(2), the piperazine ring possesses inversion symmetry and has a chair conformation. Its mean plane makes a dihedral angle of 65.45 (7)degrees with the 4-nitrophenol ring. In the crystal, the piperazine ring is linked to two 4-nitrophenol molecules via O-H center dot center dot center dot N hydrogen bonds. The molecules are also linked via bifurcated N-H center dot center dot center dot(O, O) hydrogen bonds involving the NO2 O atoms, forming a two-dimensional network lying parallel to (102). The networks are linked via C-H center dot center dot center dot O hydrogen bonds, forming a three-dimensional structure.