Oxidatively-induced aromatic cyanation mediated by Ni(iii)
Wen Zhou1, Nigam P Rath, Liviu M Mirica
1Department of Chemistry, Washington University, One Brookings Drive, St. Louis, Missouri 63130-4899, USA. mirica@wustl.edu.
Dalton Transactions (Cambridge, England : 2003)
|February 5, 2016
Summary
A novel nickel complex facilitates aromatic cyanation through an oxidative process. This reaction involves the heterolytic cleavage of a nitrogen-tert-butyl bond, mediated by a nickel(III) intermediate.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Synthetic Chemistry
Background:
- Nickel complexes are versatile catalysts in organic synthesis.
- Isocyanide ligands offer unique reactivity in coordination chemistry.
- Tetradentate ligands provide robust coordination environments for metal centers.
Purpose of the Study:
- To synthesize and characterize a new Ni(II) complex with t-butylisocyanide ligands.
- To investigate the catalytic activity of this complex in aromatic cyanation reactions.
- To elucidate the mechanism of the oxidatively-induced cyanation process.
Main Methods:
- Synthesis and characterization of a Ni(II) tetradentate complex.
- Oxidation reactions with the Ni(II) complex and t-butylisocyanide.
- Spectroscopic and reactivity studies to determine the reaction mechanism.
Main Results:
- Successful synthesis of the target Ni(II) complex.
- Quantitative yield of aromatic cyanation product upon oxidation.
- Evidence for a Ni(III) intermediate mediating the reaction via N-(t)Bu bond cleavage.
Conclusions:
- The Ni(II) complex is an effective precursor for oxidative cyanation.
- The reaction proceeds through a Ni(III) species involving heterolytic bond cleavage.
- This study expands the scope of nickel-catalyzed cyanation reactions.
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