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Title: On the reciprocal relationship between σ-hole bonding and (anti)aromaticity gain in ketocyclopolyenes
σ-Hole bonding interactions ( e.g. , tetrel, pnictogen, chalcogen, and halogen bonding) can polarize π-electrons to enhance cyclic [4 n ] π-electron delocalization ( i.e. , antiaromaticity gain) or cyclic [4 n + 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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Organic & Biomolecular Chemistry
Page Range or eLocation-ID:
5125 to 5129
Sponsoring Org:
National Science Foundation
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