Diaquabis[5-(2-pyrazin-2-yl)tetrazolato]copper(II)–pyrazine-2-carbonitrile (1/2)

Abstract

The title compound, [Cu(C5H3N6)2(H2O)2]·2C5H3N3, is a 1:2 co-crystal between the mononuclear complex di­aqua­bis­[5-(pyrazin-2-yl)tetra­zolato]copper(II) and the reagent pyrazine-2-carbo­nitrile which was used in the synthesis. The CuII atom is located on an inversion centre and has a distorted octa­hedral [4 + 2]-coordination environment formed by four N atoms of two chelating bidentate 5-(pyrazin-2-yl)tetra­zolate ligands at shorter distances and two water O atoms at longer distances. The CuII complex molecules are held together by O—H⋯N hydrogen bonds and π–π stacking inter­actions [centroid–centroid distance 3.6139 (8) Å], forming layers parallel to (100). These layers alternate with layers of pyrazine-2-car­bo­nitrile mol­ecules and both are held together via C—H⋯N hydrogen bonds and further π–π stacking inter­actions.

Syntheses and crystal structures of two magnesium–tetrazole compounds in salt and polymeric forms

“…The O-Mg-O angles in 5-(pyridinium-3yl)tetrazol-1-ide hexaaquamagnesium dichloride (Dai & Chen, 2011) are in good agreement with those found in (II), whereas the Mg-O bond lengths range from 2.0526 (14) to 2.0965 (16) Å and from 2.0496 (13) to 2.1231 (16) Å for the two compounds, respectively. The angles in the monoanion of (II) cover the range 104.40 (16)-125.38 (17) and the distances vary from 1.325 (2) to 1.482 (3) Å ; these values are similar to those found in other structures with the same ligand (Li et al, 2007;Tao et al, 2008;Bensegueni et al, 2014). The C-N and N-N bonds in (II) indicate a delocalized -aromatic system in the tetrazolate rings, similar to that found in compound (I).…”

“…Metal comlexes of these two ligands are known for their fascinating structures, which is why we have focused our research interests on the synthesis of compounds of this type in an attempt to obtain structures with new network topologies (Bensegueni et al, 2014). In this paper, we report the syntheses, crystal structures and network studies of a novel salt and a polymer containing tetrazole ligands and magnesium alkaline earth ions.…”