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Updated: Dec 17, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
On the reciprocal relationship between σ-hole bonding and (anti)aromaticity gain in ketocyclopolyenes
Hari Ram Paudel1, Lucas José Karas1, Judy I-Chia Wu1
1Department of Chemistry, University of Houston, Houston, TX 77204, USA. jiwu@central.uh.edu.
Abstract:
σ-Hole bonding interactions (e.g., tetrel, pnictogen, chalcogen, and halogen bonding) can polarize π-electrons to enhance cyclic [4n] π-electron delocalization (i.e., antiaromaticity gain) or cyclic [4n + 2] π-electron delocalization (i.e., aromaticity gain). Examples based on the ketocyclopolyenes: cyclopentadienone, tropone, and planar cyclononatetraenone are presented. Recognizing this relationship has implications, for example, for tuning the electronic properties of fulvene-based π-conjugated systems such as 9-fluorenone.
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