Triazole based copper(II) complexes: Synthesis, spectroscopic characterization, Density Function Theory study, and biomimicking of copper containing oxidase proteins

Abstract

Within the framework of the present study, a polydentate ligand with S and N donor sites along with its CuII‐based chelates were prepared and characterized. Elemental and thermal analyses, μeff and ΛM measurements as well as spectroscopy techniques including FT‐IR, electronic spectra, and EPR are the characterization tools. Computational chemistry calculations were applied to confirm the geometrical assignments of the penta and hexa coordinated perchlorato and chloro derivatives, respectively. Octahedral and trigonal bipyramidal stereochemistries were assigned for these copper(II) chelates. Powder X‐ray spectroscopy data were processed by Expo 2014 computer program for the structural illustration of one of the existing octahedral metal complexes. Biomimicking of copper(II) containing proteins phenoxazinone synthase and catechol oxidase was studied and the obtained results demonstrated promising oxidase‐like activity of the present CuII‐base complexes. Kinetic measurements were also performed to identify the potential catalytic pathways of the studied oxidation processes. The type of the counter‐anion included in the complexes significantly controls the structural features and the catalytic properties.

Structural and bio-catalytic aspects of nano crystallite iron(iii) complexes containing triazole-based ligands

“…Nowadays, XRD data processing of microcrystalline samples of metallic complexes by Expo 2014 combined with Rietveld's method 55 has become an alternative technique for X-ray single crystal structural analysis. 7,26,27,56…”

“…The computed values (Table 6) of cell dimensions such as a , b and c in Å and α , β and γ in (°), cell volume (Å 3 ), density (g cm −3 ) and Rietveld results are acceptable and comparable with those reported for similar cases. 7,26,27,56…”

“…Nowadays, XRD data processing of microcrystalline samples of metallic complexes by Expo 2014 combined with Rietveld's method 55 has become an alternative technique for X-ray single crystal structural analysis. 7,26,27,56 Fig. 4 shows the X-ray powder diffraction spectrum of complex 1 while the spectra of the other complexes 2 and 3 are given in S26 and S31 (ESI †).…”

“…A survey of the literature shows the scarcity of participation of either triazole or quinoxaline in the ligand systems of metal complexes used in biomimetic chemistry studies. 14,25–27…”

“…A survey of the literature shows the scarcity of participation of either triazole or quinoxaline in the ligand systems of metal complexes used in biomimetic chemistry studies. 14,[25][26][27] In the course of our efforts to model non-heme iron enzymes we synthesize three triazole-based iron(III) complexes as functional models of catechol oxidase and phenoxazinone synthase.…”