Synthesis, crystal structure and magnetic properties of a Cu(II) paddle-wheel complex with mixed bridges

• A new mixed carboxylate copper paddle-wheel, [Cu(μ-Pip)(μ-MeCO2)(MeOH)]2 is reported.
• Structure analysis revealed a supramolecular 2D network supported by hydrogen bonds.
• Strong antiferromagnetic Cu ⋯ Cu interaction (J = − 308 cm− 1), favored by the four bridging carboxylates.

The synthesis and characterization of a mixed carboxylate paddle-wheel copper complex, with formula [Cu(μ-Pip)(μ-MeCO2)(MeOH)]2 (Pip = piperonylate or 1,3-benzodioxole-5-carboxylate and MeCO2 = acetate), is here reported. The described compound is a binuclear complex, each pair of similar carboxylate ligands occupying mutually trans bridging positions, while the methanol occupies the apical positions. The dimers are arranged into 2D layers in the bc plane through a network of O-H ⋯ O hydrogen bonds established between the methanol and the acetate ligand. Magnetic studies showed a strong antiferromagnetic Cu ⋯ Cu interaction (J = − 308 cm− 1), in agreement with the presence of four μ-κO-κO′ carboxylates bridging the metallic centers in the binuclear complex.

Synthesis and characterization of a copper(II) mixed carboxylate paddle wheel compound.Figure optionsDownload as PowerPoint slide