Bridging the Bays, Both Ways: A Janus Butterfly-Shaped Intense NIR-Emitting Terrylene Diimide

Area of Science:

• Organic Chemistry
• Materials Science
• Photophysics

Background:

• Molecules with near-infrared (NIR) emission are crucial for applications like night vision and bio-imaging.
• Current synthesis of such molecules often involves complex procedures.
• Developing efficient and accessible NIR emitters remains a significant challenge.

Purpose of the Study:

• To present a straightforward strategy for synthesizing novel Janus butterfly-shaped terrylene diimide (TDI) derivatives.
• To investigate the photophysical properties of these new TDI derivatives, focusing on NIR emission.
• To establish a correlation between molecular structure and emission efficiency.

Main Methods:

• Synthesis of unsymmetrical terrylene diimide (TDI) derivatives with carbazole wings.
• Characterization of the synthesized compounds using spectroscopic and structural techniques.
• Evaluation of photophysical properties, including absorption, emission spectra, and quantum yields.

Main Results:

• Successful synthesis of novel Janus butterfly-shaped TDI derivatives with carbazole wings.
• Observation of intense NIR absorption and emission in the synthesized compounds.
• Achieved impressive emission quantum yields up to 93% for unsymmetrically substituted TDIs, the highest reported for this class.
• Identified minimal structural distortion correlating with high emission efficiency.
• Reported a novel two-tiered TDI-carbazole with intense emission at 897 nm.

Conclusions:

• A simple and effective strategy for creating efficient NIR luminophores has been demonstrated.
• Precise functionalization of terrylene diimide derivatives leads to high-performance NIR emitters.
• The developed compounds hold promise for advanced applications requiring intense NIR emission.