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Abstract We introduce the heterocumulene ligand [(Ad)NCC(tBu)]−(Ad=1‐adamantyl (C10H15),tBu=tert‐butyl, (C4H9)), which can adopt two forms, the azaalleneyl and ynamide. This ligand platform can undergo a reversible chelotropic shift using Brønsted acid‐base chemistry, which promotes an unprecedented spin‐state change of the [VIII] ion. These unique scaffolds are prepared via addition of 1‐adamantyl isonitrile (C≡NAd) across the alkylidyne in complexes [(BDI)V≡CtBu(OTf)] (A) (BDI−=ArNC(CH3)CHC(CH3)NAr), Ar=2,6‐iPr2C6H3) and [(dBDI)V≡CtBu(OEt2)] (B) (dBDI2−=ArNC(CH3)CHC(CH2)NAr). ComplexAreacts with C≡NAd, to generate the high‐spin [VIII] complex with a κ1‐N‐ynamide ligand, [(BDI)V{κ1‐N‐(Ad)NCC(tBu)}(OTf)] (1). Conversely,Breacts with C≡NAd to generate a low‐spin [VIII] diamagnetic complex having a chelated κ2‐C,N‐azaalleneyl ligand, [(dBDI)V{κ2‐N,C‐(Ad)NCC(tBu)}] (2). Theoretical studies have been applied to better understand the mechanism of formation of2and the electronic reconfiguration upon structural rearrangement by the alteration of ligand denticity between1and2.
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Exploring Spin‐Orbit Effects in a [Cu 6 Tl] + Nanocluster Featuring an Uncommon Tl−H Interaction
Abstract Reaction of [CuH(PPh3)]6with 1 equiv. of Tl(OTf) results in formation of [Cu6TlH6(PPh3)6][OTf] ([1]OTf]), which can be isolated in good yields. Variable‐temperature1H NMR spectroscopy, in combination with density functional theory (DFT) calculations, confirms the presence of a rare Tl−H orbital interaction. According to DFT, the1H chemical shift of the Tl‐adjacent hydride ligands of[1]+includes 7.7 ppm of deshielding due to spin‐orbit effects from the heavy Tl atom. This study provides valuable new insights into a rare class of metal hydrides, given that[1][OTf]is only the third isolable species reported to contain a Tl−H interaction.
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- Award ID(s):
- 2055063
- PAR ID:
- 10495250
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- ISSN:
- 0947-6539
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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