Synthesis and structural studies of novel Cu(II) complexes with hydroxy derivatives of benzo[b]furan and coumarin

A series of new Cu(II) complexes with the hydroxy derivatives of benzo[b]furan and coumarin have been electrochemically synthesized. The geometry of the metal–ligand interaction has been described using the single crystal X-ray diffraction method and X-ray absorption spectroscopy. Two ligands are bonded to the metal cation via the acetyl and deprotonated hydroxyl O atoms. The centrosymmetric coordination polyhedron of Cu(II) exhibits a square-planar geometry (CuO4), with both ligands coordinating in the chelating mode.

Graphical abstractThe Cu(II) cation is four- coordinated in five complexes with the hydroxy derivatives of benzo[b]furan and coumarin. The complexes have been studied by the XAFS analysis and the X-ray crystallography.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Electrochemical synthesis of Cu(II) complexes with hydroxy derivatives of benzo[b]furan and coumarin. ► Metal–ligand interactions were studied by X-ray crystal structure analysis and X-ray absorption spectroscopy. ► Five mononuclear complexes were obtained; four with benzo[b]furan ligands and one with hydroxycoumarin. ► In all the complexes Cu(II) is chelated by two anionic ligands and the CuO4 environment shows a square-planar geometry.