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Abstract The incorporation of cationic groups onto electron‐poor compounds is a viable strategy for achieving potent electron acceptors, as evidenced by reports of air‐stable radical forms of large aromatic diimides such as naphthalene and perylene diimides. These ions have also been observed to exhibit anion–π interaction tendencies of interest in molecular recognition applications. The benefits of phosphonium incorporation, however, have not yet been extended to the smallest benzene diimides. Here, we report that dibrominated pyromellitic diimide and mellophanic diimide both readily undergo substitution reactions with phosphine sources to yield bisphosphonium compounds. In the single crystalline form, these dications display anion‐π interactions and, in the case of mellophanic diimide, the stabilization of a bromide–water H−bonding ring pattern. The reaction of these dications with chemical reductants readily provides the singly and doubly reduced redox states, which were characterized by UV‐vis spectroscopy and found to exhibit intense absorptions extending into the near‐IR region. Taken together, this work demonstrates that phosphonium incorporation onto congested aromatic diimide scaffolds is synthetically viable and produces unusual electron‐poor compounds. 

We report the synthesis and characterization of naphthalene and anthracene scaffolds end-capped by cyclic imides. The solid-state structures of theN-phenyl derivatives, determined by X-ray crystallography, reveal changes in packing preference based on the number of aromatic rings in the core. The optical and electronic properties of the title compounds compare favorably with other previously described isomers and expand the toolbox of electron-deficient aromatic compounds available to organic materials chemists. 

Abstract This work presents the 2^ndgeneration ofcata‐annulated azaacene bisimides with increased electron affinities (up to −4.38 eV) compared to their consaguine conventional azaacenes. These compounds were synthesized via Buchwald–Hartwig coupling followed by oxidation with MnO₂. Crystal structure engineering through variation of the bisimide substituents furnished crystalline derivatives suitable forproof of conceptorganic field effect transistors with electron mobilities up to 2.2×10⁻⁴ cm²(Vs)⁻¹. Moreover, we were able to characterize the charge carrying species, the radical anion, using electron paramagnetic resonance and absorption measurements.