Reversible Nucleophilic Ring-Opening of Tetraoxapentacene Derivatives: Accessing New Materials for Thermally Activated Delayed Fluorescence

We report the unexpected nucleophilic ring-opening reaction of electron deficient dioxins in the presence of carbazole under basic conditions. This nucleophilic ring-opening reaction is reversible under basic conditions in the absence of nucleophiles. Further, we demonstrate that this unexpected reactivity can be used to prepare novel donor–acceptor compounds that are emissive in solution and as thin films and exhibit thermally activated delayed fluorescence (TADF).