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Chemiluminescence-based Assays for Detection of Nitric Oxide and its Derivatives from Autoxidation and Nitrosated Compounds
Published on: February 16, 2022
Nitric oxide release from a nickel nitrosyl complex induced by one-electron oxidation
Ashley M Wright1, Homaira T Zaman, Guang Wu
1Department of Chemistry and Biochemistry, University of California-Santa Barbara, Santa Barbara, California 93106, USA.
Inorganic Chemistry
|February 26, 2013
Summary
The reaction of a nickel-nitrosyl complex with oxidants reveals varied denitrosylation pathways. TEMPO oxidation cleaves the Ni-NO bond, generating NO, while diphenyldisulfide forms an adduct.
Area of Science:
- Organometallic Chemistry
- Coordination Chemistry
- Inorganic Chemistry
Background:
- Nickel-nitrosyl complexes are important in catalysis and materials science.
- Understanding the reactivity of the Ni-NO bond is crucial for designing new transformations.
Purpose of the Study:
- To investigate the denitrosylation reactions of a specific nickel-nitrosyl complex, [Ni(NO)(bipy)][PF6].
- To explore the influence of different oxidants on the Ni-NO bond cleavage and product formation.
Main Methods:
- Reaction of [Ni(NO)(bipy)][PF6] with various oxidants: AgPF6, [NO][PF6], Ph2S2, TEMPO, and pyridine-N-oxide.
- Isolation and characterization of reaction products using spectroscopic and crystallographic techniques.
- Analysis of redox potentials to explain observed reactivity differences.
Main Results:
- AgPF6 and [NO][PF6] induce denitrosylation, releasing NO gas.
- Ph2S2 forms a diphenyldisulfide adduct without denitrosylation, highlighting its weaker oxidizing potential.
- TEMPO oxidation leads to efficient Ni-NO bond cleavage and formation of a [(bipy)Ni(η(2)-TEMPO)][PF6] complex.
- Pyridine-N-oxide forms an adduct, with no NO release observed due to its low reduction potential.
Conclusions:
- The reactivity of nickel-nitrosyl complexes towards oxidants is highly dependent on the oxidant's redox potential.
- TEMPO is an effective oxidant for Ni-NO bond cleavage, yielding stable metal-TEMPO complexes.
- This study provides insights into selective denitrosylation and adduct formation pathways in organonickel chemistry.
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