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Hexa‐tert‐butyl‐carbo‐benzene (C₁₈tBu₆) and three phenylated counterparts (C₁₈tBu_mPh_6−m; m=4, 2) have been synthesized. The peralkylated version (m=6) provides experimental access to intrinsic features of the insulated C₁₈ core independently from the influence of π‐conjugated substituent. Over the series, structural, spectroscopic, and electrochemical properties are compared with those of the hexaphenylated reference (m=0). Anchoring tBu substituents at the C₁₈ macrocycle is shown to enhance stability and solubility, and to dramatically modify UV/Vis absorption and redox properties. Whereas all carbo‐benzenes reported previously were obtained as dark‐reddish/greenish solids, crystals and solutions of C₁₈tBu₆ happen to be yellow (λ_max=379 vs. 472 nm for C₁₈Ph₆). In comparison to C₁₈Ph₆, the reduction of C₁₈tBu₆ remains reversible, but occurs at twice as high an absolute potential (E_1/2=−1 …