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Abstract Cyclotetrabenzil, a shape‐persistent macrocyclic octaketone, is found to undergo eightfold condensation with hydroxylamine hydrochloride to yield its octaoxime. Subsequent acetylation of this macrocyclic oxime afforded the corresponding octaoxime acetate. Single‐crystal X‐ray diffraction reveals that both new derivatives assemble into nanotubular structures. However, their packing differs: the oxime forms hydrogen‐bonded tubes that bundle via included dimethyl sulfoxide (DMSO) molecules, whereas the acetate—lacking hydrogen‐bond donors—forms more loosely packed tubes with molecules tilted ∼54.5° relative to the tube axis. Gas sorption studies (CO₂, C₂, and C₃hydrocarbons) show that cyclotetrabenzil is nonporous, whereas the oxime and acetate exhibit modest microporosity with BET surface areas of ∼200 m²g⁻¹. Both derivatives display preferential uptake of propyne over propene and propane, and the acetate also adsorbs more acetylene than ethylene or ethane. Nonetheless, these capacities and selectivities are suboptimal for dynamic separation of C₂and C₃hydrocarbons. This study illustrates how oxime functionalization can modulate macrocyclic assembly and gas uptake behavior, providing insights for the design of future porous organic macrocycles. 

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.