New Electron-Rich Polycyclic 1,2-BN-Heteroarenes with Phenyl Spacer: Synthesis and Photophysical Properties
Disciplines
Materials Chemistry | Organic Chemistry | Physical Chemistry
Abstract (300 words maximum)
Incorporating a B–N bond into polycyclic aromatic hydrocarbons generates planar azaborine scaffolds with unique optoelectronic features, including high photochemical stability, strong absorption, high fluorescence quantum yields, large Stokes shifts, and tunable emission. These attributes make BN-substituted heteroarenes promising candidates for applications such as organic light-emitting diodes (OLEDs) and related optoelectronic devices. However, enhancing electron density and controlling conjugation without compromising stability remain significant challenges. To address this, we designed and synthesized new electron-rich polycyclic 1,2-BN-heteroarenes incorporating strong electron-donating groups, including carbazole and dimethylaminodiphenyl, attached through a phenyl spacer. This design improves conjugation, introduces steric modulation, and enables control over charge-transfer interactions while mitigating aggregation-caused quenching (ACQ) of emission. Using palladium-catalyzed cross-coupling method, we successfully synthesized two target compounds featuring extended π-systems and enhanced donor–acceptor character. We propose that the phenyl spacer and bulky substituents reduce ACQ, improve photophysical stability, and yield tunable optical responses with potential multi-stimuli responsiveness. These structural modifications highlight a versatile strategy for tailoring BN-based heteroarenes. Beyond OLEDs, such multifunctional chromophores hold promise for chemical and biological sensors, adaptive optoelectronic systems, and security applications, expanding the utility of BN-embedded materials in next-generation technologies.
Use of AI Disclaimer
no
Academic department under which the project should be listed
CSM – Chemistry and Biochemistry
Primary Investigator (PI) Name
Carl J. Saint-Louis
New Electron-Rich Polycyclic 1,2-BN-Heteroarenes with Phenyl Spacer: Synthesis and Photophysical Properties
Incorporating a B–N bond into polycyclic aromatic hydrocarbons generates planar azaborine scaffolds with unique optoelectronic features, including high photochemical stability, strong absorption, high fluorescence quantum yields, large Stokes shifts, and tunable emission. These attributes make BN-substituted heteroarenes promising candidates for applications such as organic light-emitting diodes (OLEDs) and related optoelectronic devices. However, enhancing electron density and controlling conjugation without compromising stability remain significant challenges. To address this, we designed and synthesized new electron-rich polycyclic 1,2-BN-heteroarenes incorporating strong electron-donating groups, including carbazole and dimethylaminodiphenyl, attached through a phenyl spacer. This design improves conjugation, introduces steric modulation, and enables control over charge-transfer interactions while mitigating aggregation-caused quenching (ACQ) of emission. Using palladium-catalyzed cross-coupling method, we successfully synthesized two target compounds featuring extended π-systems and enhanced donor–acceptor character. We propose that the phenyl spacer and bulky substituents reduce ACQ, improve photophysical stability, and yield tunable optical responses with potential multi-stimuli responsiveness. These structural modifications highlight a versatile strategy for tailoring BN-based heteroarenes. Beyond OLEDs, such multifunctional chromophores hold promise for chemical and biological sensors, adaptive optoelectronic systems, and security applications, expanding the utility of BN-embedded materials in next-generation technologies.