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Stimuli-Responsive Multifunctional Iridium(III) Complex Exhibiting Thermo-, Vapochromism, and Double Catalytic
Ekaterina V Nykhrikova1,2, Marina A Kiseleva1, Paulina Kalle1
1N.S. Kurnakov Institute of General and Inorganic Chemistry, Russian Academy of Sciences, Leninskii pr. 31, Moscow 119991, Russia.
Inorganic Chemistry
|February 24, 2025
Summary
This study introduces a novel iridium(III) complex that reversibly changes its structure with temperature and solvent. This molecular switch enables unique vapochromic and catalytic properties, offering new possibilities in materials science.
Area of Science:
- Organometallic Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Designing multifunctional compounds responsive to external stimuli is a significant challenge.
- Cyclometalated iridium(III) complexes offer tunable properties for various applications.
Purpose of the Study:
- To synthesize and characterize a novel cyclometalated iridium(III) complex with switchable molecular geometry.
- To investigate the stimuli-responsive behavior and resulting properties of the complex.
Main Methods:
- Synthesis of a bulky 1,2-diphenylphenanthroimidazole iridium(III) complex.
- Variable-temperature 1H NMR, single-crystal and powder X-ray diffraction.
- Density functional theory (DFT) calculations, UV-vis titration.
Main Results:
- The iridium(III) complex exhibits reversible monomer-dimer transformations triggered by temperature and solvent.
- Structural changes lead to thermochromic behavior in solution and solid states.
- The monomeric form shows reversible vapochromism and switchable catalytic activity.
Conclusions:
- The developed iridium(III) complex acts as a molecular switch, demonstrating tunable structural and functional properties.
- This work presents a new platform for stimuli-responsive materials with potential in sensing and catalysis.
- The complex's ability to switch between states unlocks unprecedented functionalities, including catalysis for transfer hydrogenation and reductive debromination.
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