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

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.This work was partially financed by the Spanish National Plan of ResearchCTQ2014-56324 and Severo OchoaSEV-2015-0496, and by the 2014SGR260 and 2014SGR377 projects from the Generalitat de Catalunya.Peer reviewe