Modular Access to Boron Tripyrrolic Complexes from a Sequential Buchwald-Hartwig Amination/Boron Complexation...

Area of Science:

• Organic Chemistry
• Materials Science
• Biophysical Chemistry

Background:

• Boron-containing organic molecules are of interest for their unique photophysical properties.
• Pyrromethene derivatives are known fluorophores, but their functionalization can be challenging.
• Developing new synthetic routes for complex organic molecules is crucial for advancing materials science.

Purpose of the Study:

• To report a modular synthesis of novel boron tripyrrolic analogs (BOTPY).
• To explore the synthesis of structurally diverse BOTPY derivatives.
• To evaluate the photophysical properties and imaging capabilities of the synthesized BOTPY compounds.

Main Methods:

• A sequential Buchwald-Hartwig amination followed by boron complexation reaction.
• Utilizing readily accessible α,α-dibromodipyrromethenes as starting materials.
• Characterization of synthesized compounds using standard spectroscopic techniques.

Main Results:

• Successful synthesis of B-, meso-, and α-positionally functionalized BOTPY fluorophores.
• Achieved tunable absorption and fluorescence emission in the visible to near-infrared (NIR) region.
• Demonstrated high fluorescence quantum yields (Φ_F up to 0.36).
• Showcased applicability of BOTPY analogs for lipid droplet imaging.

Conclusions:

• The reported synthetic strategy provides facile access to a range of BOTPY derivatives.
• BOTPY compounds exhibit promising photophysical properties for optical applications.
• The developed fluorophores are suitable for biological imaging, specifically lipid droplet visualization.