Various starting precursors can be used in a multicomponent condensation reaction to obtain differently substituted imidazole derivatives with structural diversity easily installed at the N1, C2, and C4/5 ring positions. Typical synthesis routes for imidazole-containing emitter materials introduce electron donor, or π-spacer and donor groups at C2. These groups tend to be conjugated with the imidazole, as arenes such as phenylene rings adopt a relatively co-planar conformation. By contrast, phenylene substituents at C5 or N1 adopt a significantly more twisted conformation. Most of the reported examples of D-A compounds involving imidazole include a C2-substituted imidazole, these compounds emit either via fluorescence or a hot exciton channel mechanism as the excited state possesses mixed hybridized local and charge-transfer (HLCT) character. There are only a small number of acridine-dicyanoimidazole derivatives that were reported as thermally activated delayed fluorescent (TADF) emitters (Figure , Table ).