χ‑Shaped Bis(areno)-1,4-dihydropyrrolo[3,2‑b]pyrroles Generated by Oxidative Aromatic Coupling

A synthesis of dihydropyrrolo­[3,2-b]­pyrroles fused with two peripheral arenes or heterocyclic units has been realized through the concise route. These nearly planar compounds were prepared starting from assembling the central core via condensation of 2-aryl or 2-heteroarylbenzaldehydes with aromatic amines and diacetyl, followed by double intramolecular oxidative aromatic coupling. This two-step procedure afforded the desired products in overall yields of 5–36%, and it tolerates structural diversity of starting materials. All the final dyes exhibit strong blue fluorescence in solution.