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Preparation of Stable Bicyclic Aziridinium Ions and Their Ring-Opening for the Synthesis of Azaheterocycles
Published on: August 22, 2018
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Enantiopure [6]-Azairidahelicene by Dynamic Kinetic Resolution of a Configurationally Labile [4]-Helicene
Ariadna Pazos1, Carlos M Cruz2, Juan M Cuerva2
1Department of Applied Chemistry, Faculty of Chemistry, University of the Basque Country (UPV/EHU), 20018, Donostia, Spain.
Angewandte Chemie (International Ed. in English)
|April 24, 2024
Summary
Researchers synthesized enantiopure azairidaphenanthrenes using dynamic kinetic resolution. These compounds exhibit circularly polarized phosphorescence, demonstrating chirality transfer from metal to ligand.
Area of Science:
- Coordination Chemistry
- Organic Synthesis
- Photophysics
Background:
- Helicenes are chiral aromatic compounds with unique photophysical properties.
- Chirality transfer in metal complexes is crucial for developing advanced materials.
- Dynamic kinetic resolution (DKR) offers a powerful route to enantiopure compounds from racemic mixtures.
Purpose of the Study:
- To synthesize enantiopure [6]-azairidahelicenes with chirality at both the metal center and helicenic ligand.
- To investigate the mechanism of dynamic kinetic resolution in this system.
- To explore the circularly polarized phosphorescence (CPP) properties of the synthesized compounds.
Main Methods:
- Dynamic kinetic resolution (DKR) of a configurationally labile [4]-helicenic ligand.
- Synthesis using bis-cyclometalated chiral-at-metal iridium(III) precursors.
- Characterization of enantiopure azairidaphenanthrenes and their photophysical properties.
Main Results:
- Successful synthesis of enantiopure [6]-azairidahelicenes.
- Demonstration of chirality transfer from iridium(III) precursors to the helicenic ligand.
- Observation of circularly polarized phosphorescence (CPP) with |gphos| values up to 1.8×10-3.
- Attribution of DKR to conformational differences in diastereomeric intermediates.
Conclusions:
- Enantiopure azairidaphenanthrenes can be accessed via DKR.
- The iridium(III) precursors effectively induce chirality transfer.
- The synthesized compounds are promising for applications in circularly polarized luminescence.
Keywords:
Chiral-at-metal ComplexesCircularly Polarized LuminescenceHelical StructuresIridiumKinetic resolutionMore Related Videos
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