Ítem


Modulation of a μ-1,2-Peroxo Dicopper(II) Intermediate by Strong Interaction with Alkali Metal Ions

The properties of metal/dioxygen species, which are key intermediates in oxidation catalysis, can be modulated by interaction with redox-inactive Lewis acids, but structural information about these adducts is scarce. Here we demonstrate that even mildly Lewis acidic alkali metal ions, which are typically viewed as innocent ’spectators’, bind strongly to a reactive cis-peroxo dicopper(II) intermediate. Unprecedented structural insight has now been obtained from X-ray crystallographic characterization of the ’bare’ CuII2(μ-η1:η1-O2) motif and its Li+, Na+, and K+ complexes. UV-vis, Raman, and electrochemical studies show that the binding persists in MeCN solution, growing stronger in proportion to the cation’s Lewis acidity. The affinity for Li+ is surprisingly high (∼70 × 104 M-1), leading to Li+ extraction from its crown ether complex. Computational analysis indicates that the alkali ions influence the entire Cu-OO-Cu core, modulating the degree of charge transfer from copper to dioxygen. This induces significant changes in the electronic, magnetic, and electrochemical signatures of the Cu2O2 species. These findings have far-reaching implications for analyses of transient metal/dioxygen intermediates, which are often studied in situ, and they may be relevant to many (bio)chemical oxidation processes when considering the widespread presence of alkali cations in synthetic and natural environments

American Chemical Society (ACS)

Autor: Brinkmeier, Alexander
Dalle, Kristian E.
D’Amore, Lorenzo
Schulz, Roland A.
Dechert, Sebastian
Demeshko, Serhiy
Swart, Marcel
Meyer, Franc
Data: 18 octubre 2021
Resum: The properties of metal/dioxygen species, which are key intermediates in oxidation catalysis, can be modulated by interaction with redox-inactive Lewis acids, but structural information about these adducts is scarce. Here we demonstrate that even mildly Lewis acidic alkali metal ions, which are typically viewed as innocent ’spectators’, bind strongly to a reactive cis-peroxo dicopper(II) intermediate. Unprecedented structural insight has now been obtained from X-ray crystallographic characterization of the ’bare’ CuII2(μ-η1:η1-O2) motif and its Li+, Na+, and K+ complexes. UV-vis, Raman, and electrochemical studies show that the binding persists in MeCN solution, growing stronger in proportion to the cation’s Lewis acidity. The affinity for Li+ is surprisingly high (∼70 × 104 M-1), leading to Li+ extraction from its crown ether complex. Computational analysis indicates that the alkali ions influence the entire Cu-OO-Cu core, modulating the degree of charge transfer from copper to dioxygen. This induces significant changes in the electronic, magnetic, and electrochemical signatures of the Cu2O2 species. These findings have far-reaching implications for analyses of transient metal/dioxygen intermediates, which are often studied in situ, and they may be relevant to many (bio)chemical oxidation processes when considering the widespread presence of alkali cations in synthetic and natural environments
Format: application/pdf
Accés al document: http://hdl.handle.net/10256/22388
Llenguatge: eng
Editor: American Chemical Society (ACS)
Col·lecció: info:eu-repo/semantics/altIdentifier/doi/10.1021/jacs.1c08645
info:eu-repo/semantics/altIdentifier/issn/0002-7863
info:eu-repo/semantics/altIdentifier/eissn/1520-5126
Drets: Tots els drets reservats
Matèria: Metalls alcalins
Cations
Ions
Àcids de Lewis
Alkali metals
Cations
Ions
Lewis acids
Títol: Modulation of a μ-1,2-Peroxo Dicopper(II) Intermediate by Strong Interaction with Alkali Metal Ions
Tipus: info:eu-repo/semantics/article
Repositori: DUGiDocs

Matèries

Autors