Acenaphthylene-Cored D–π–A-Type Molecules for Organic Light-Emitting Diodes

Luminescent organic molecules play a pivotal role in the advancement of organic light-emitting diode (OLED) materials. Herein, a class of acenaphthylene-cored D–π–A-type molecules were designed and synthesized (isolated yields >85% for each step), wherein the acenaphthylene served as a conjugated bridge integrating a benzoxazole acceptor moiety and a triarylamine donor unit. Computational results showed a spatially segregated distribution of the frontier molecular orbitals, which achieved a small singlet–triplet energy gap (ΔEST = 0.1 eV). The corresponding OLED device emitted green light at 543 nm. Furthermore, this work represents the first combined application of acenaphthylene and benzoxazole in luminescent organic materials.