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Pairing multicomponent stators with aromatic rotators for new emissive molecular rotors
Ma Carmen García-González1, Jorge Espinosa-Rocha1, Lizbeth A Rodríguez-Cortés1
1Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior S.N., Ciudad Universitaria, Coyoacán, Ciudad de México 04510, Mexico. lmiranda@unam.mx brodriguez@iquimica.unam.mx.
Organic & Biomolecular Chemistry
|April 26, 2021
Summary
Researchers synthesized novel molecular rotors using the Ugi-Sonogashira protocol, creating highly fluorescent compounds sensitive to environmental changes like aggregation and viscosity.
Area of Science:
- Organic Chemistry
- Materials Science
- Photophysics
Background:
- Molecular rotors are crucial for developing advanced materials.
- Understanding structure-property relationships is key for designing functional molecules.
Purpose of the Study:
- To synthesize novel molecular rotors using the Ugi-Sonogashira protocol.
- To investigate the photophysical properties of these new compounds.
- To explore their sensitivity to environmental stimuli.
Main Methods:
- Utilized the Ugi-Sonogashira multicomponent reaction.
- Combined Ugi stators with aromatic rotary components (phenylene, p-xylene, naphthalene, anthracene).
- Characterized the synthesized compounds' fluorescence and environmental responses.
Main Results:
- Successfully synthesized five new molecular rotors (10a-e).
- Achieved high fluorescence quantum yields (Φf = 0.39 to 0.10).
- Observed emission changes in response to aggregation (THF/water) and high viscosity (methanol/glycerol).
Conclusions:
- The Ugi-Sonogashira protocol is effective for creating emissive molecular rotors.
- The synthesized rotors exhibit tunable photophysical properties based on their environment.
- These findings open avenues for developing new fluorescent materials with tailored applications.
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