Molecular engineering of high-performance TADF emitters via Buchwald-Hartwig amination for OLED applications

Abstract

Thermally activated delayed fluorescence (TADF) emitters, capable of harvesting both singlet and triplet excitons for 100% internal quantum efficiency, represent a cornerstone of third-generation OLED technology. The development of these materials critically depends on robust and versatile synthetic methodologies. This review highlights the central role of palladium-catalyzed Buchwald-Hartwig amination in constructing sophisticated TADF architecture. We systematically examine the role of this pivotal synthetic tool in enabling the precise fabrication of TADF materials across a structural hierarchy, from donor-acceptor and multiple-resonance small molecules to conformationally rigid macrocycles, and further to solution-processable polymers. The discussion directly links molecular design enabled by C-N bond formation, with key photophysical properties and ultimately with device performance metrics in OLEDs. Finally, we outline a rational design framework and future challenges, emphasizing the need for innovative synthetic approaches and advanced material designs to meet the escalating demands for efficiency, stability, color purity, and processability in next-generation displays and lighting.