Molecular and Electronic Structures of Eight-Coordinate Uranium Bipyridine Complexes: A Rare Example of a Bipy2– Ligand Coordinated to a U4+ Ion
| Autor: | Frank W. Heinemann, Karsten Meyer, Michael W. Rosenzweig, Laurent Maron |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
010405 organic chemistry
Chemistry Ligand Cryptand Inorganic chemistry chemistry.chemical_element Electronic structure Uranium 010402 general chemistry Electrochemistry 01 natural sciences 0104 chemical sciences law.invention Ion Inorganic Chemistry Crystallography Bipyridine chemistry.chemical_compound law Physical and Theoretical Chemistry Electron paramagnetic resonance |
| Zdroj: | Inorganic Chemistry. 56:2792-2800 |
| ISSN: | 1520-510X 0020-1669 |
| DOI: | 10.1021/acs.inorgchem.6b02954 |
| Popis: | Reaction of trivalent [((Ad,tBuArO)3tacn)U] (1) with 2,2′-bipyridine (bipy) yields [((Ad,tBuArO)3tacn)U(bipy)] (2) and subsequent reduction of 2 with KC8 in the presence of Kryptofix222 furnishes [K(2.2.2-crypt)][((Ad,tBuArO)3tacn)U(bipy)] (3). Alternatively, complex 3 can be synthesized from 1 by addition of [K(bipy)] in the presence of the cryptand. New complexes 2 and 3 are characterized by a variety of spectroscopic, electrochemical, and magnetochemical methods, single-crystal X-ray diffraction, computational methods, and CHN elemental analysis. Structural analyses reveal a bipyridine radical (bipy•–) ligand in 2 and a dianionic (bipy2–) species in 3. Complex 3 represents a rare example of an isolated and unambiguously characterized bipy2– ligand coordinated to a uranium ion. The electronic structure assignments are supported by UV/vis/NIR and EPR spectroscopy, as well as SQUID magnetometry. The results of CASSCF calculations indicate multiconfigurational ground states for complexes 2 and 3. The elect... |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|