A Route to Stabilize Uranium(II) and Uranium(I) Synthons in Multimetallic Complexes
R A Keerthi Shivaraam1, Megan Keener1, Dieuwertje K Modder1
1Group of Coordination Chemistry, Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
Angewandte Chemie (International Ed. in English)
|April 4, 2023
Summary
Researchers stabilized low-valent uranium synthons using a novel intramolecular ligand migration mechanism. This discovery offers new control over the redox reactivity of unstable metal centers, advancing f-element chemistry.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Uranium Chemistry
Background:
- Low-valent metal complexes are often unstable and challenging to synthesize.
- Controlling redox reactivity is crucial for developing new catalytic and materials applications.
- Uranium's unique electronic structure offers potential for novel reactivity.
Purpose of the Study:
- To investigate the redox behavior of a multimetallic uranium complex.
- To explore the stabilization of low-valent uranium species.
- To understand the role of ligand migration in redox processes.
Main Methods:
- Synthesis and characterization of a diuranium(IV) complex with triphenylsiloxide ligands.
- Electrochemical reduction studies to induce electron transfer.
- Spectroscopic and crystallographic analysis of reduced products.
Main Results:
- Two- and three-electron reduction of the diuranium(IV) complex yielded U(II)/U(IV) and U(I)/U(IV) species.
- Intramolecular ligand migration was observed during reduction, forming uranium-arene δ-bonds.
- A reduced complex facilitated the reductive coupling of pyridine, accompanied by ligand migration.
Conclusions:
- A novel mechanism for stabilizing low-valent uranium synthons via ligand migration was identified.
- This approach provides a new strategy for controlling redox reactivity in f-element complexes.
- The findings pave the way for further exploration of f-elements' redox chemistry.
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