Construction of two mercury(II) coordination frameworks involving in situ tetrazole ligand synthesis

Two novel mercury(II)-organic polymeric complexes [HgCl(pzta)]n (1) and [Hg3Cl2(pzta)4(H2O)2]n (2) [pzta = pyrazinyl tetrazolate] were obtained by in situ synthesis of pyrazinyl tetrazolate from the reaction of pyrazinecarbonitrile with sodium azide in the presence of mercury(II) salts. Complex 1 is a 3D coordination polymer with a 3,5-connected hms [(63)(69 · 8)] net consisting of mildly undulate (6, 3) sheets and bridging chlorine ligands; while complex 2 is also a 3D supramolecular network built from 2D layers with the 4-connected sql {44 · 62} net that are assembled via hydrogen bonds and π⋯π stacking interactions. Last but not least, photofluorescent properties of the two complexes have also been investigated.