A five-coordinate Ni(I) complex supported by 1,4,7-triisopropyl-1,4,7-triazacyclononane
Leonel Griego1, Toby J Woods1, Liviu M Mirica1
1Department of Chemistry University of Illinois at Urbana Champaign 600 S. Mathews Avenue, Urbana, Illinois, 61801, USA. mirica@illinois.edu.
Chemical Communications (Cambridge, England)
|June 16, 2022
Summary
Researchers synthesized a novel nickel-nitrosyl complex using a bulky ligand. This work advances the understanding of nickel-nitrosyl chemistry and the isolation of unusual nickel complexes.
Area of Science:
- Inorganic Chemistry
- Organometallic Chemistry
- Coordination Chemistry
Background:
- Nickel nitrosyl complexes are of interest due to their potential applications in catalysis and their unique electronic properties.
- The synthesis and characterization of low-coordinate nickel complexes present significant challenges.
- Bulky ligands like 1,4,7-triisopropyl-1,4,7-triazacyclononane (iPr3TACN) are crucial for stabilizing reactive metal centers.
Purpose of the Study:
- To synthesize and characterize a novel nickel-nitrosyl complex.
- To investigate the reactivity of nickel complexes with nitrosyl sources.
- To explore the formation of unusual low-coordinate nickel species.
Main Methods:
- Reaction of a Ni(II) dimethyl complex with NOPF6.
- Isolation and characterization of the resulting nickel-nitrosyl complex.
- Use of a π-acceptor ancillary isocyanide ligand (tert-butylisocyanide) to stabilize a 5-coordinate Ni(I) complex.
Main Results:
- Successful isolation of a Ni(II)-nitrosyl complex supported by the bulky iPr3TACN ligand.
- Evidence for the *in situ* formation of a Ni(I) species reacting with NO.
- Characterization of a rare 5-coordinate Ni(I) complex featuring the iPr3TACN ligand and tert-butylisocyanide.
Conclusions:
- The bulky iPr3TACN ligand is effective in supporting nickel-nitrosyl complexes.
- This study demonstrates a pathway to accessing unusual Ni(I) species.
- The findings contribute to the fundamental understanding of nickel coordination chemistry and nitrosyl ligand interactions.
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