Actinide tetra-N-heterocyclic carbene 'sandwiches'.
Chem Sci
; 12(22): 7882-7887, 2021 May 10.
Article
em En
| MEDLINE
| ID: mdl-34168841
ABSTRACT
Highly-symmetrical, thorium and uranium octakis-carbene 'sandwich' complexes have been prepared by 'sandwiching' the An(iv) cations between two anionic macrocyclic tetra-NHC ligands, one with sixteen atoms and the other with eighteen atoms. The complexes were characterized by a range of experimental methods and DFT calculations. X-ray crystallography confirms the geometry at the metal centre can be set by the size of the macrocyclic ring, leading to either square prismatic or square anti-prismatic shapes; the geometry of the latter is retained in solution, which also undergoes reversible, electrochemical one-electron oxidation or reduction for the uranium variant. DFT calculations reveal a frontier orbital picture that is similar to thorocene and uranocene, in which the NHC ligands show almost exclusively σ-donation to the metal without π-backbonding.
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Base de dados:
MEDLINE
Idioma:
En
Revista:
Chem Sci
Ano de publicação:
2021
Tipo de documento:
Article