AbstractPyrrole‐modified subporphyrins bearing a non‐pyrrolic cyclic unit, subporpholactone, subporpholactam, and imidazolosubporphyrin were newly synthesized. They show subporphyrin‐like absorption and fluorescence spectra that are red‐shifted in the order of subporpholactam<subporpholactone<imidazolosubporphyrin. Metalation of the imidazolosubporphyrin with (pentamethylcyclopentadienyl)iridium(III) dichloride dimer gave a complex, in which the iridium(III) atom was attached at the peripheral nitrogen atom of the imidazole moiety and the ortho‐position of the meso‐phenyl group. Reaction of this complex with diphenylacetylene gave different products depending on the used additive; a phenyl‐rearranged product in the presence of NaBArF4 (ArF=3,5‐bis(trifluoromethyl)phenyl) and two isomeric carbene complexes in the presence of KPF6.