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Accessing [g]-Face π-Expanded Fluorescent Coumarins by Scholl Cyclization.
Nitisha1, Parthasarathy Venkatakrishnan1
1Department of Chemistry , Indian Institute of Technology Madras , Chennai 600036 , Tamil Nadu , India.
The Journal of Organic Chemistry
|August 21, 2019
Summary
New [g]-face π-expanded coumarins were synthesized using Scholl cyclization. These compounds exhibit promising fluorescent properties and photostability for bioimaging applications.
Area of Science:
- Organic Chemistry
- Materials Science
- Photophysics
Background:
- Coumarins are a versatile class of organic compounds with diverse applications.
- Developing novel coumarin derivatives with enhanced photophysical properties is crucial for advanced technologies.
- Arene-annulated structures can significantly influence electronic and optical characteristics.
Purpose of the Study:
- To synthesize novel [g]-face π-expanded coumarins.
- To investigate the absorption and fluorescent properties of these new compounds.
- To evaluate their potential for bioimaging applications.
Main Methods:
- Synthesis via Scholl cyclization.
- Characterization of photophysical properties (absorption and fluorescence).
- Assessment of photostability and quantum yields.
Main Results:
- Successful synthesis of [g]-face π-expanded coumarins.
- Observation of interesting absorption and fluorescence spectra.
- Demonstration of large Stokes shifts, tuneable quantum yields, and high photostability.
Conclusions:
- The synthesized coumarins possess desirable photophysical characteristics.
- These properties make them promising candidates for bioimaging.
- Scholl cyclization is an effective method for creating such π-expanded systems.
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