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Aromaticity and antiaromaticity are pivotal concepts in chemistry, with significant implications for molecular properties and reactivity. 

Abstract Whether tetra‐tert‐butyl‐s‐indacene is a symmetricD_2hstructure or a bond‐alternatingC_2hstructure remains a standing puzzle. Close agreement between experimental and computed proton chemical shifts based on minima structures optimized at the M06‐2X, ωB97X‐D, and M11 levels confirm a bond‐localizedC_2hsymmetry, which is consistent with the expected strong antiaromaticity of TtB‐s‐indacene. 

Abstract Two new partially fluorinated dehydrobenzannulenes have been prepared by inter‐ and intramolecular oxidative homocoupling of diyne precursors. These systems contain fluorinated and nonfluorinated arene rings in a desymmetrized non‐alternant arrangement. Both macrocycles are roughly planar and organize into extended columns in the solid state. The assembly of these columns is mediated by the combination of dispersion interactions, slipped [π⋅⋅⋅π] stacking interactions of the perfluorinated rings with each other, and their association with the nonfluorinated rings in the molecules of the neighboring macrocycles. These results suggest that partial fluorination of dehydrobenzannulenes can serve as a versatile motif for their assembly into columnar superstructures. 

Abstract Organic electrode materials could revolutionize batteries because of their high energy densities, the use of Earth‐abundant elements, and structural diversity which allows fine‐tuning of electrochemical properties. However, small organic molecules and intermediates formed during their redox cycling in lithium‐ion batteries (LIBs) have high solubility in organic electrolytes, leading to rapid decay of cycling performance. We report the use of three cyclotetrabenzil octaketone macrocycles as cathode materials for LIBs. The rigid and insoluble naphthalene‐based cyclotetrabenzil reversibly accepts eight electrons in a two‐step process with a specific capacity of 279 mAh g⁻¹and a stable cycling performance with ≈65 % capacity retention after 135 cycles. DFT calculations indicate that its reduction increases both ring strain and ring rigidity, as demonstrated by computed high distortion energies, repulsive regions in NCI plots, and close [C⋅⋅⋅C] contacts between the naphthalenes. This work highlights the importance of shape‐persistency and ring strain in the design of redox‐active macrocycles that maintain very low solubility in various redox states.