Observation of a Cu II 2 (μ‐1,2‐peroxo)/Cu III 2 (μ‐oxo) 2 Equilibrium and its Implications for Copper–Dioxygen Reactivity
Year: 2014
Type: article
Abstract: Synthesis of small-molecule Cu2 O2 adducts has provided insight into the related biological systems and their reactivity patterns including the interconversion of the Cu(II) 2 (μ-η(2) :η(2) -peroxo) and Cu(III) 2 (μ-oxo)2 isomers. In this study, absorption spectroscopy, kinetics, and resonance Raman data show that the oxygenated product of [(BQPA)Cu(I) ](+) initially yields an "end-on peroxo" species, that subsequently converts to the thermodynamically more stable "bis-μ-oxo" isomer (Keq =3.2 at -90 °C). Calibration of density functional theory calculations to these experimental data suggest that the electrophilic reactivity previously ascribed to end-on peroxo species is in fact a result of an accessible bis-μ-oxo isomer, an electrophilic Cu2 O2 isomer in contrast to the nucleophilic reactivity of binuclear Cu(II) end-on peroxo species. This study is the first report of the interconversion of an end-on peroxo to bis-μ-oxo species in transition metal-dioxygen chemistry.
Language: English
Subfield: Inorganic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
Awards: G1744233332, G2513652571, Bioinorganic Copper Coordination Chemistry, Heme/Copper and Heme/Nonheme Iron O(2) and NO Reactivity, Spectroscopic Studies of Active Sites in Copper Proteins, Spectroscopic and Computational Investigation of Cytrochrome C Oxidase and Models, G7081875245, Mechanistic Intermediates in Copper Oxygenases and Oxidases
OpenAlex ID: W2136635537