Synthesis, spectroscopy, and electrochemistry of copper(II) complexes with N,N '-bis(3,5-di-t-butylsalicylideneimine) polymethylenediamine ligands

Kasumov V., Koksal F.

SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY, vol.61, no.1-2, pp.225-231, 2005 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 61 Issue: 1-2
  • Publication Date: 2005
  • Doi Number: 10.1016/j.saa.2004.03.037
  • Journal Name: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.225-231
  • Keywords: bulky polymethylene-salen Cu(II) complexes, spectroscopy, electrochemistry, ELECTRON-SPIN-RESONANCE, MAGNETIC EXCHANGE, SPECTRA, SALEN, IONS, ESR, SALICYLALDEHYDE, SUBSTITUENTS, PARAMETERS, CATALYSIS
  • Ondokuz Mayıs University Affiliated: No

Abstract

Bulky salen CuLx derived from aliphatic polymethylene diamines, H2N-(CH2)(x)-NH2, where n = 2-6, and 3,5-di-t-butylsalicylaldehyde (H2Lx) and some corresponding tetrahydrosalan complexes (CuL'(x)) have been synthesized and characterized by their IR, UV-vis absorption and EPR spectra, by magnetic moments and by cyclic voltammetry in acetonitrile (for H2Lx) and DMF (for CuLx). Complexes CuLx and CuL'(x) are magnetically normal (mu(exp) = 1.83-1.91 mu(B)). EPR spectra CuLx characterized by the axial g and A(Cu) tensors with g(parallel to) > g(perpendicular to) and without N-14-shf resolution in CHCl3/toluene at 300 and 150 K. The CV studies on acetonitrile solutions of H2Lx revealed a well-defined quasi-reversible redox wave at E-1/2 = 0.95-1.15 V versus Ag/AgCl but CV of the CuLx complexes in DMF exhibit weak pronounced irreversible oxidation waves at E-pa(1) = 0.51 - 0.98 V and E-pa(2) = 1.16 - 1.33 V attributable to metal centered Cu(II/III) and ligand centered CuLx/CuLx.+ couples, respectively. A poorly defined wave was observed for the quasi-reversible reduction Cu(II)/Cu(I) at potentials less than -1.0 V. (C) 2004 Elsevier B.V. All rights reserved.