861394-89-0Relevant academic research and scientific papers
Synthesis, spectroscopic and redox properties of a novel series of copper(II) complexes of N-alkyl-3,5-Bu2t-salicylaldimines. Generation of the directly coordinated Cu(II)-phenoxyl radical complexes
Kasumov, Veli T.,K?ksal, Fevzi,Sezer, Ali
, p. 1203 - 1211 (2005)
A series of novel copper(II) complexes, X, with N-R-3,5-Bu2t- salicylaldimines, derived from 3,5-Bu2t-salicylaldehyde and alkylamines (RNH2) have been prepared and their spectroscopic (IR, UV-Vis, ESR), magnetic and redox reactivity are described. ESR spectral parameters and μeff values suggest that complexes are magnetically diluted in the solid state. The CV of some X exhibits a dependence of CuII/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)2Ce(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 CuII 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.
Synthesis and X-ray structural characterization of sterically hindered bis(3,5-di-tert-butylsalicylaldiminato)Cu(II) complexes
Ahmad, Jahir Uddin,Raeisaenen, Minna T.,Nieger, Martin,Sundberg, Markku R.,Figiel, Pawel J.,Leskelae, Markku,Repo, Timo
, p. 205 - 212 (2012/06/30)
Bis(3,5-di-tert-butylsalicylaldiminato)Cu(II) complexes were prepared in high yields from a sterically hindered 3,5-di-tert-butylsalicylaldehyde and a variety of amines using three synthetic approaches. They were all thoroughly characterized by various spectroscopic methods (UV-Vis, IR, EPR and EI-MS). Crystal structures of seven complexes determined by X-ray crystallography show the Cu ion in a N2O2 coordination environment and a tetrahedrally distorted square-planar geometry. The UV-Vis and EPR results indicated that the complexes have the same geometry also in solution. In two solid state structures of the complexes the ligands have obtained an unusual cis-orientation whereas the rest of the complexes are trans-isomers. Computational studies carried out by the density functional theory method verified that in the case of complex with N-alkyl fragment the preferred isomer is trans, while the opposite behavior is observed for the complex with N-phenyl substituent.
