Original scientific paper

https://doi.org/10.5562/cca3334

Chalcone and Flavonol Copper(II) Complexes Containing Schiff Base Co-Ligand: Synthesis, Crystal Structures and Catecholase-like Activity

Emira Kahrović orcid.org/0000-0001-9067-3556 ; Department of Chemistry, Faculty of Science, University of Sarajevo, Zmaja od Bosne 33-35, BA-71000 Sarajevo, Bosnia and Herzegovina
Adnan Zahirović orcid.org/0000-0001-7662-3341 ; Department of Chemistry, Faculty of Science, University of Sarajevo, Zmaja od Bosne 33-35, BA-71000 Sarajevo, Bosnia and Herzegovina
Aleksandar Višnjevac ; Laboratory for Chemical and Biological Crystallography, Ruđer Bošković Institute, Bijenička cesta 54, HR-10000 Zagreb, Croatia
Irnesa Osmanković orcid.org/0000-0003-0536-7728 ; Department of Chemistry, Faculty of Science, University of Sarajevo, Zmaja od Bosne 33-35, BA-71000 Sarajevo, Bosnia and Herzegovina
Emir Turkušić ; Department of Chemistry, Faculty of Science, University of Sarajevo, Zmaja od Bosne 33-35, BA-71000 Sarajevo, Bosnia and Herzegovina
Harun Kurtagić ; Federal Institute of Agriculture, Butmirska cesta 40, BA-71000 Sarajevo, Bosnia and Herzegovina

Abstract

Four new heteroleptic copper(II) complexes having chalcone or flavonol ligands and Schiff base (N-phenyl-5-chlorosalicylideneimine) as co-ligand were prepared, chemically and structurally characterized and investigated as functional biomimetic catecholase models. The complexes were prepared by the solution synthesis and crystal and molecular structures were determined by X-ray diffraction. Complexes were chemically characterized by elemental analysis, infrared and electronic absorption spectroscopy as well as by electrochemical measurements. Copper(II) chalcone complexes, with square-pyramidal CuO4N core, are binuclear, featuring phenolate oxygen from the Schiff base as a bridging atom, while copper(II) flavonol complexes are mononuclear, and reveal a square planar CuO3N coordination core. Catalytic activity of the complexes in 3,5-di-tert-butylcatechol oxidation was confirmed by spectrophotometric and electrochemical measurements. Kinetic measurements revealed that the binuclear (chalcone-containing) complexes have enhanced catalytic activity as compared to the mononuclear Cu(II) flavonol complexes. Relatively high kcat values (300 – 750 h–1) confirmed their respectable biomimetic catecholase-like activity.

This work is licensed under a Creative Commons Attribution 4.0 International License.

Keywords

copper; Schiff base; chalcone; flavonol; catecholase activity

Hrčak ID:

202087

URI

https://hrcak.srce.hr/202087

Publication date:

4.6.2018.

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