Synthesis, spectroscopic and redox properties of a novel series of copper(II) complexes of N-alkyl-3,5-Bu-2(t)-salicylaldimines. Generation of the directly coordinated Cu(II)-phenoxyl radical complexes

Kasumov V., Koksal F., Sezer A.

POLYHEDRON, vol.24, no.10, pp.1203-1211, 2005 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 24 Issue: 10
  • Publication Date: 2005
  • Doi Number: 10.1016/j.poly.2005.04.003
  • Journal Name: POLYHEDRON
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Index Chemicus (IC)
  • Page Numbers: pp.1203-1211
  • Keywords: bis(N-alkyl-3,5-Bu-2(t)-salicylaldiminato)copper(II) complexes, spectroscopy, electrochemistry, Cu(II)-phenoxyl radical complexes, ELECTRON-SPIN-RESONANCE, SCHIFF-BASE COMPLEXES, GALACTOSE-OXIDASE, AEROBIC OXIDATION, METAL-COMPLEXES, PRIMARY ALCOHOLS, SPECTRA, REDUCTION, CHEMISTRY, LIGANDS
  • Ondokuz Mayıs University Affiliated: No

Abstract

A series of novel copper(II) complexes, X, with N-R-3,5-Bu-2'-salicylaldimines, derived from 3,5-Bu-2'-salicylaldehyde and alkyl-amines (RNH2) have been prepared and their spectroscopic (IR, UV-Vis, ESR), magnetic and redox reactivity are described. ESR spectral parameters and mu(eff) values suggest that complexes are magnetically diluted in the solid state. The CV of some X exhibits a dependence of Cu-II/Cu-I potentials on bulkiness R groups, but the ligand centered oxidation potentials are less influenced by the nature of R. In the chemical oxidation of X with 8-10-fold excess (NH4)(2)Ce(NO3)(6) in CHCl3 at 300 K, besides decreasing ESR signal of X, the appearance of a new broad lines centered at ca. g = 2.116-2.217 and radical signals (g = 2.0048 - 2.0086) assigned to new Cu-II centers and Cu(II)-phenoxyl radicals, respectively, were detected. UV-Vis spectra revealed new maxima at 630-790 nm for all oxidized X complexes and a very weak shoulder at ca. 800-830 nm for some of them. (c) 2005 Elsevier Ltd. All rights reserved.