Fluorinated Organic Paramagnetic Building Blocks for Cross-Coupling Reactions.
Larisa V Politanskaya1, Pavel A Fedyushin1, Tatyana V Rybalova1
1N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, 9 Ac. Lavrentiev Avenue, 630090 Novosibirsk, Russia.
Molecules (Basel, Switzerland)
|November 24, 2020
Summary
New stable polyfluorinated nitroxide radicals were synthesized for cross-coupling reactions. These radicals form unique one-dimensional and zero-dimensional assemblies, influencing their magnetic properties.
Area of Science:
- Organic Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Stable nitroxide radicals are valuable in various chemical applications.
- Polyfluorinated aromatic compounds offer unique electronic properties.
- Halogen bonding and metal coordination are key strategies in supramolecular chemistry.
Purpose of the Study:
- To synthesize novel stable polyfluorinated nitroxide radicals.
- To investigate the self-assembly behavior of these radicals through halogen bonding.
- To explore the magnetic properties of complexes formed by these radicals with metal ions.
Main Methods:
- Synthesis of polyfluorinated nitroxide radicals from perfluoroiodobenzene.
- Characterization of radical structures and self-assembly via N-O···I halogen bonds.
- Coordination chemistry with Cu(hfac)2 to form multi-spin complexes.
Main Results:
- Successful preparation of N-tert-butyl-N-oxyamino-2,3,5,6-tetrafluoro-4-iodobenzene and N-tert-butyl-N-oxyamino-2,3,5,6-tetrafluoro-4-ethynylbenzene.
- Observation of one-dimensional radical assembly in the solid state through N-O···I halogen bonds.
- Formation of a zero-dimensional three-spin complex with ferromagnetic intramolecular exchange interactions.
Conclusions:
- The synthesized polyfluorinated nitroxide radicals are stable and versatile building blocks.
- Halogen bonding dictates the supramolecular assembly of these radicals in the solid state.
- Coordination with metal centers leads to novel magnetic properties due to spin interactions.
Keywords:
aromatic nucleophilic substitutionfluoroarenesfunctionalized nitroxidesstable organic radicalstert-butylarylnitroxidesMore Related Videos
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