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Updated: Mar 10, 2026
10:52
Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
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Arrested α-hydride migration activates a phosphido ligand for C-H insertion
Anne K Hickey1, Salvador B Muñoz1, Sean A Lutz1
1Department of Chemistry, Indiana University, Bloomington, Indiana 47401, USA. smith962@indiana.edu.
Chemical Communications (Cambridge, England)
|December 14, 2016
Summary
Bulky tris(carbene)borate ligands create high-spin iron(II) phosphido complexes. These complexes show instability, with [PPh] group transfer reactivity driven by phosphorus nucleophilicity.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Ligand Design
Background:
- Bulky tris(carbene)borate ligands are effective in stabilizing unusual coordination numbers and electronic configurations in metal complexes.
- Iron(II) phosphido complexes are of interest due to their potential applications in catalysis and materials science.
Purpose of the Study:
- To synthesize and characterize high-spin iron(II) phosphido complexes using bulky tris(carbene)borate ligands.
- To investigate the reactivity and stability of these novel iron complexes.
Main Methods:
- Synthesis of iron(II) phosphido complexes supported by tris(carbene)borate ligands.
- Characterization using spectroscopic techniques (e.g., NMR, X-ray crystallography).
- Thermal stability studies and mechanistic investigations of decomposition pathways.
Main Results:
- Successful synthesis of a high-spin iron(II) phosphido complex, PhB(MesIm)3FeP(H)Ph.
- Observation of thermal instability, leading to [PPh] group insertion into a C-H bond of the supporting ligand.
- Evidence for an arrested α-hydride migration mechanism governing the observed reactivity.
Conclusions:
- Bulky tris(carbene)borate ligands enable access to high-spin iron(II) phosphido species.
- The observed [PPh] group transfer reactivity is facilitated by the increased nucleophilicity of the phosphorus atom.
- An arrested α-hydride migration pathway provides insight into the decomposition mechanism of these complexes.
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