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Reversible O-O bond cleavage in copper-dioxygen isomers: impact of anion basicity.

ABSTRACT: Low-temperature oxygenation of copper(I) complexes of N,N,N',N'-tetraethylpropane-1,3-diamine yields solutions containing both mu-eta2:eta2-peroxodicopper(II) (P) and bis(mu-oxo)dicopper(III) (O) valence isomers. The P/O equilibrium position depends on the nature of the counteranion; P is favored with more basic anions. Titration and EXAFS experiments as well as DFT calculations suggest that axial donation from a sulfonate anion to the copper centers imparts an electronic/electrostatic bias toward the P isomer.

SUBMITTER: Ottenwaelder X

PROVIDER: S-EPMC2526018 | biostudies-literature | 2006 Jul

REPOSITORIES: biostudies-literature

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Reversible O-O bond cleavage in copper-dioxygen isomers: impact of anion basicity.

Ottenwaelder Xavier X Rudd Deanne Jackson DJ Corbett Mary C MC Hodgson Keith O KO Hedman Britt B Stack T Daniel P TD

Journal of the American Chemical Society 20060701 29

Low-temperature oxygenation of copper(I) complexes of N,N,N',N'-tetraethylpropane-1,3-diamine yields solutions containing both mu-eta2:eta2-peroxodicopper(II) (P) and bis(mu-oxo)dicopper(III) (O) valence isomers. The P/O equilibrium position depends on the nature of the counteranion; P is favored with more basic anions. Titration and EXAFS experiments as well as DFT calculations suggest that axial donation from a sulfonate anion to the copper centers imparts an electronic/electrostatic bias towa ...[more]

PMID: 16848427

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