80662-61-9Relevant academic research and scientific papers
Electron spin resonance and electrochemical study of thiohydroxamate and 1-phenyl-3-imino-2(1H)-pyridinethione complexes of copper(II)
Becher, Jan,Brockway, David J.,Murray, Keith S.,Newman, Peter J.,Toftlund, Hans
, p. 1791 - 1798 (1982)
Syntheses, electronic spectra, ESR spectra, and electrochemical properties are described for a range of {S,O} chelates of copper(II)-containing bidentate thiohydroxamic acids, viz., Cu(RC(=S)N(R′)O)2, and for two tetredentate {S,N} 1-phenyl-3-imino-2(1H)-pyridinethione complexes. Both classes of compounds have square-planar geometries; the thiohydroxamates have a trans-{S2,O2} chromophore while the pyridinethione derivatives have a cis-{S2,N2} chromophore. S → Cu(II) charge-transfer bands are observed in the UV-visible spectra. Unusual solvent-dependent changes in the visible spectra are displayed by the R′ = H thiohydroxamates. The ESR spectra of the thiohydroxamate complexes give well-resolved lines with narrow line widths. Some unusual splittings of the parallel lines in the frozen solution spectra and in the four-line fluid solution spectra are observed. The ESR spectra of the Cu{S2,N2} complex show broader and less well-resolved line shapes. Polographic and cyclic voltammetric measurements on DMF solutions of the compounds are discussed in detail. The Cu(II)/Cu(I) reduction potentials are compared with those of related thio complexes and with those of copper redox proteins. A brief discussion of the likely binding groups in the active sites of copper proteins is given.
