Donor–Acceptor Iptycenes with Thermally Activated Delayed Fluorescence

Abstract

A new donor–acceptor iptycene containing carbazole donors and a thiadiazoloquinoxaline acceptor was synthesized and its photo- and electrochemical properties evaluated. The key intermediate 1 allows a lateral modification through cross-coupling, and the (triisopropylsilyl)acetylene product 2 exhibits bright yellow fluorescence with emission lifetimes of 2.42 µs in deoxygenated hexane. The long lifetime and high quantum efficiency (73 %) is quenched by O2 and therefore attributed to thermally activated delayed fluorescence (TADF). This approach allows functionalization through cross-coupling reactions and depicts a promising scaffold for the synthesis of TADF-active molecules.