1-Piperonylpiperazinium 4-nitro-benzoate monohydrate

Abstract

IN THE TITLE HYDRATED SALT [SYSTEMATIC NAME: 1-(1,3-benzodioxol-5-ylmeth-yl)piperazin-1-ium 4-nitro-benzoate monohydrate], C12H17N2O2 (+)·C7H4NO4 (-)·H2O, the piperazinium ring of the cation adopts a slightly distorted chair conformation. The piperonyl and piperazine rings are rotated with respect to each other with an N-C-C-C torsion angle of 45.6 (2)°. In the anion, the nitro group is almost coplanar with the adjacent benzene ring, forming a dihedral angle of only 3.9 (4)°. In the crystal, the cations, anions and water mol-ecules are linked through N-H⋯O and O-H⋯O hydrogen bonds into chains along the a axis. In addition, weaker inter-molecular C-H⋯O inter-actions are also observed within the chains. The anions form centrosymmetric couples through π-stacking inter-actions, with an inter-centroid distance of 3.681 (4) Å between the benzene rings.

Fig. 1.

ORTEP drawing of one independent monocation-monoanion-water molecule unit in the asymmetric unit of (I) (C12H17N2O2+ . C7H4NO4- . H2O) showing the labeling scheme with 30% probability displacement ellipsoids.

Fig. 2.

Molecular packing for (I) viewed along the b axis. Dashed lines indicate N—H···O, O—H···O intermolecular hydrogen bonds and weak C—H···O intermolecular interactions. H atoms not involved in hydrogen bonding have been removed for clarity.