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Published on: June 10, 2021
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Fluorescence from bisaryl-substituted maleimide derivatives
Milena Helmer Lauer1, Roberta Lopes Drekener, Carlos Roque Duarte Correia
1Institute of Chemistry of São Carlos, University of São Paulo, CEP 13560-590, São Carlos, SP, Brazil. marcelog@iqsc.usp.br.
Summary
Researchers synthesized novel bisaryl-substituted fluorescent maleimides using Heck arylation. These compounds exhibit tunable fluorescence properties and significant excited-state dipole moments, indicating potential applications in materials science.
Area of Science:
- Organic Chemistry
- Photophysics
- Materials Science
Background:
- Fluorescent organic molecules are crucial for various applications.
- Maleimide derivatives offer versatile synthetic platforms.
- Understanding structure-property relationships is key for designing new materials.
Purpose of the Study:
- To synthesize and characterize novel bisaryl-substituted fluorescent maleimides.
- To investigate their photophysical properties, including fluorescence emission, Stokes shift, and quantum yield.
- To explore the influence of molecular structure and solvent polarity on these properties.
Main Methods:
- Heck arylation for synthesis of bisaryl-substituted maleimides.
- Spectroscopic techniques (UV-Vis absorption, fluorescence emission) for photophysical characterization.
- Time-resolved fluorescence spectroscopy to study excited-state dynamics.
Main Results:
- Successful synthesis of bisaryl-substituted fluorescent maleimides with broad visible emission.
- Observed large Stokes shifts in polar solvents and quantum yields ranging from 0.04 to 0.71.
- Determined excited-state dipole moments of approximately 12 Debye, indicating significant charge transfer.
- Biexponential fluorescence decays observed in polar solvents, suggesting complex excited-state processes.
Conclusions:
- Bisaryl-substituted maleimides are promising fluorescent materials with tunable properties.
- Charge transfer and push-pull character significantly influence their photophysical behavior.
- Solvent polarity and specific structural features dictate excited-state dynamics, including potential proton transfer.
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