IC Th U Cb R2.pdf (1.13 MB)
Thorium- and uranium-mediated C-H activation of a silyl-substituted cyclobutadienyl ligand
journal contribution
posted on 2023-06-10, 05:46 authored by Nikolaos Tsoureas, Thayalan Rajeshkumar, Oliver PE Townrow, Laurent Maron, Richard LayfieldRichard LayfieldCyclobutadienyl complexes of the f-elements are a relatively new yet poorly understood class of sandwich and half-sandwich organometallic compounds. We now describe cyclobutadienyl transfer reactions of the magnesium reagent [(?4-Cb'''')Mg(THF)3] (1), where Cb'''' is tetrakis(trimethylsilyl)cyclobutadienyl, toward thorium(IV) and uranium(IV) tetrachlorides. The 1:1 stoichiometric reactions between 1 and AnCl4 proceed with intact transfer of Cb'''' to give the half-sandwich complexes [(?4-Cb'''')AnCl(µ-Cl)3Mg(THF)3] (An = Th, 2; An = U, 3). Using a 2:1 reaction stoichiometry produces [Mg2Cl3(THF)6][(?4-Cb'''')An(?3-C4H(SiMe3)3-?-(CH2SiMe2)(Cl)] (An = Th, [Mg2Cl3(THF)6][4]; An = U [Mg2Cl3(THF)6][5]), in which one Cb'''' ligand has undergone cyclometalation of a trimethylsilyl group, resulting in the formation of an An-C s-bond, protonation of the four-membered ring, and an ?3-allylic interaction with the actinide. Complex solution-phase dynamics are observed with multinuclear nuclear magnetic resonance spectroscopy for both sandwich complexes. A computational analysis of the reaction mechanism leading to the formation of 4 and 5 indicates that the cyclobutadienyl ligands undergo C-H activation across the actinide center.
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- Published
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- Accepted version
Journal
Inorganic ChemistryISSN
0020-1669Publisher
American Chemical Society (ACS)External DOI
Issue
50Volume
61Page range
20629-20635Event location
United StatesDepartment affiliated with
- Chemistry Publications
Full text available
- No
Peer reviewed?
- Yes
Legacy Posted Date
2023-01-04First Compliant Deposit (FCD) Date
2022-12-20Usage metrics
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