Polyanils and Polyboranils: Synthesis, Optical Properties, and Aggregation-Induced Emission

Area of Science:

• Organic Chemistry
• Materials Science
• Photophysics

Background:

• Polyanils are a class of organic compounds with potential applications in materials science.
• Developing novel fluorophores with tunable optical properties is crucial for advanced optical and electronic devices.
• Boron-containing compounds are of interest for their unique chemical and physical characteristics.

Purpose of the Study:

• To synthesize novel polyanils and their corresponding boranil derivatives.
• To investigate the optical properties of these novel fluorophores, including their emission across the visible and near-infrared spectrum.
• To explore the aggregation-induced emission (AIE) behavior of selected polyanils.

Main Methods:

• Synthesis of polyanils via condensation reactions involving phenylenediamine derivatives or benzenetriamine with substituted salicylaldehydes, and substituted anilines with dihydroxyisophthalaldehydes or dihydroxyterephthalaldehydes.
• Chelation of trivalent boron fragments (BF2, BPh2) to form boranils.
• Spectroscopic analysis (UV-Vis absorption and fluorescence emission) in solution and solid-state, and investigation of AIE in THF/water mixtures.

Main Results:

• Successful synthesis of two series of polyanils and their subsequent conversion to boranils.
• Polyanils and boranils exhibited broad emission wavelengths spanning the visible to near-infrared regions, tunable by molecular structure and environment.
• Some polyanils displayed significant aggregation-induced emission (AIE) in aqueous THF solutions, enhancing fluorescence intensity.

Conclusions:

• The synthesized polyanils and boranils represent a novel class of fluorophores with tunable optical properties.
• These compounds demonstrate potential for applications requiring broad-spectrum emission and stimuli-responsive fluorescence.
• The observed AIE behavior opens avenues for developing advanced fluorescent materials for sensing and imaging.