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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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This content will become publicly available on November 1, 2026
Crystal structure of a μ-oxo vanadium(V) dimer coordinated by a salan ligand
Aμ-oxo vanadium(V) dimeric complex, μ-oxido-bis[(2,2′-{[ethane-1,2-diylbis(azanediyl)]bis(methylene)}diphenolato)oxidovanadium(V)], [V2(C16H18N2O2)2O3] (1), was crystallized by slow evaporation from an ethanol solution. Theμ-oxo dimer crystallizes in the monoclinic space groupC2/cwhere the salan ligand1acoordinates to the vanadium center in a κ2N,κ2Ofashion, forming a distorted octahedral geometry. The bridging oxo ligand lies on a crystallographic twofold axis. The unit cell consists of four molecules of1that are linked by C—H...·πareneinteractions as well as intramolecular hydrogen bonding.
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- Award ID(s):
- 1847926
- PAR ID:
- 10651415
- Publisher / Repository:
- Acta Cryst E, Crystallographic Communications
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 81
- Issue:
- 11
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 1014 to 1017
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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