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An anionic, tetragonal copper(II) superoxide complex.

ABSTRACT: Insight into copper-oxygen species proposed as intermediates in oxidation catalysis is provided by the identification of a Cu(II)-superoxide complex supported by a sterically hindered, pyridinedicarboxamide ligand. A tetragonal, end-on superoxide structure is proposed based on DFT calculations and UV-vis, NMR, EPR, and resonance Raman spectroscopy. The complex yields a trans-1,2-peroxodicopper(II) species upon reaction with [(tmpa)Cu(CH(3)CN)]OTf and, unlike other known Cu(II)-superoxide complexes, acts as a base rather than an electrophilic (H-atom abstracting) reagent in reactions with phenols.

SUBMITTER: Donoghue PJ

PROVIDER: S-EPMC3013377 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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An anionic, tetragonal copper(II) superoxide complex.

Donoghue Patrick J PJ Gupta Aalo K AK Boyce David W DW Cramer Christopher J CJ Tolman William B WB

Journal of the American Chemical Society 20101026 45

Insight into copper-oxygen species proposed as intermediates in oxidation catalysis is provided by the identification of a Cu(II)-superoxide complex supported by a sterically hindered, pyridinedicarboxamide ligand. A tetragonal, end-on superoxide structure is proposed based on DFT calculations and UV-vis, NMR, EPR, and resonance Raman spectroscopy. The complex yields a trans-1,2-peroxodicopper(II) species upon reaction with [(tmpa)Cu(CH(3)CN)]OTf and, unlike other known Cu(II)-superoxide complex ...[more]

PMID: 20977226

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