Recently, the preparation and preliminary characterization of a new series of dioxygen complexes derived from the ligand systems N4PY2, N3PY2, and N3ORPY2 have been reported. These compounds, [Cu2L(O2)]2+ (4-6), are derived from well-characterized dicopper(I) complexes, [Cu2L]2+ (1-3), by the reversible reaction with dioxygen in dichloromethane at -80 °C (Cu:O2 = 2:1). X-ray absorption spectra of the dioxygen adducts (4-6), their dicopper(I) precursors (1-3), and other related pyridyl ligand containing Cu(I) and Cu(II) complexes are reported. The results of edge and EXAFS analysis support a description of the oxygen adducts as four- or five-coordinated peroxo-bridged dicopper(II) complexes, with Cu-Cu distances in the range 3.2-3.4 Å. Possible structures for [Cu2(L)(O2)]2+are proposed including a novel η2:η2 peroxo coordination mode. In addition, the detailed analyses of the crystallographically characterized Cu(I) precursor complexes and related Cu(II) complexes of known structure have extended to pyridyl-containing systems the validity of the multiple scattering method of EXAFS analysis (the success of which has been demonstrated recently for imidazole-containing complexes and protein derivatives).
|Original language||English (US)|
|Number of pages||10|
|Journal||Journal of the Chemical Society|
|Publication status||Published - 1988|
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