Spectral and Structural Study of two Piperazine Based Nitrate Salts

Abstract

Two new compounds, N-(2-aminoethyl)piperazinium trinitrate (AEPH3(NO3)3) and N-(2-hydroxyethyl)piperazinium dinitrate (HEPH2(NO3)2), were prepared. IR spectra of AEPH3(NO3)3 and HEPH2(NO3)2 were compared with those of the parent N-(2-aminoethyl)piperazine (AEP) and N-(2-hydroxyethyl)piperazine (HEP), respectively. The intermolecular interactions affect the symmetry of the nitrate ions in AEPH3(NO3)3 and HEPH2(NO3)2, lowering it from D3h to C2v or Cs. Single-crystal X-ray diffraction of AEPH3(NO3)3 showed that the piperazine moiety has a chair conformation and that two of its nitrogen atoms have a distorted tetrahedral geometry. Similar results were observed for HEPH2(NO3)2. In the crystals, there are N···O contacts between nitrate groups and hydrogen bond motifs between nitrate and ammonium groups (only in AEPH3(NO3)3).