Synthesis and structural characterization of copper(II) coordination polymers with 1,1,2,2-tetra(pyrazol-1-yl)ethane

• Two types of copper(II) coordination polymers with bitopic ligand were prepared.
• 1,1,2,2-tetra(pyrazol-1-yl)ethane acts as a cross-linker for {Cu(μ-NO3)} chains.
• The shortest distance between the copper(II) ions in coordination polymers is 6.85 Å.

Reaction between 1,1,2,2-tetra(pyrazol-1-yl)ethane (Pz4) and copper(II) nitrate in ethanol at room temperature and in solvothermal conditions (90 °C) lead to coordination polymers of two different structures. A ribbon-like coordination polymer {Cu2(μ2-NO3)2(H2O)4 μ′2-Pz4}n was formed at room temperature in which nitrate ions bind the monomeric units, while Pz4 ligands are responsible for cross-linking of {Cu(μ-NO3)} chains. At 90 °C linear 1D coordination polymer was formed, in which Pz4 ligands bridge copper ions that in addition bear two monodentate nitrate ions.

Two new copper(II) coordination polymers with bitopic ligand 1,1,2,2-tetra(pyrazol-1-yl)ethane were prepared and their crystal structure was determinedFigure optionsDownload as PowerPoint slide