NEW THERMALLY STABLE HYDROPEROXO-COPPER AND PEROXO-COPPER COMPLEXES

New thermally stable peroxo and hydroperoxo complexes [Cu2(UN-O-)(O2)]+ (6) and [Cu2(UN-O-)(O2H)]2+ (7) have been synthesized by oxygenation of Cu(I) precursors with an unsymmetrical dinucleating ligand UN-OH.Their stability is indicated by the ability to obtain analytical and magnetic data and solid-state UV-vis or infrared spectra and to redissolve the materials, obtaining UV-vis spectra in agreement with the species directly formed by oxygenation 'in situ". Removal of O2 from solid 6 by heating under vacuum occurs with approximately 25 decomposition. EXAFS spectroscopy of solids 6 and 7 gives Cu...Cu = 3.28 (7) and 2.95 (7) angstrom, respectively. An unsymmetrical Cu(II)-O-O...Cu(II) ligation for 6 and a mu-1,1-hydroperoxo coordination in 7 are suggested.