Donor–Acceptor Iptycenes with Thermally Activated Delayed Fluorescence

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. A new donor–acceptor iptycene scaffold is reported, which can be accessed through facile lateral modification of a key intermediate product by using the Sonogashira reaction. The (triisopropylsilyl)acetylene product is highly emissive in solution and we demonstrate that this material is TADF active.