Piperazinium bis(pyridine-2,6-dicarboxylato)mercurate(II) hexahydrate

Abstract

The reaction of mercury(II) nitrate with the proton-transfer compound (pipzH2)(pydc), where pipz is piperazine and pydcH2 is pyridine-2,6-dicarboxylic acid, in aqueous solution leads to the formation of the title compound, (pipzH2)[Hg(pydc)2]·6H2O or (C4H12N2)[Hg(C7H3NO4)2]·6H2O. The structure features six-coordinate Hg2+ (site symmetry 2) with a distorted octa­hedral geometry. Extensive inter­molecular O—H⋯O, N—H⋯O and C—H⋯O hydrogen bonding involving the (pydc)2− ligand, (pipzH2)2+ (site symmetry 2) as a counter-ion and uncoordinated water mol­ecules forms a three-dimensional network.