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Updated: Aug 23, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Conjugation between 3D and 2D aromaticity: does it really exist? The case of carborane-fused heterocycles
Dániel Buzsáki1,2, Máté Barnabás Kovács2, Evelyn Hümpfner2
1MTA-BME Computation Driven Chemistry Group Műegyetem rkp 3. H-1111 Budapest Hungary.
Abstract:
Although several synthesized icosahedral carborane fused 2D π-ring systems are known, and even considerable conjugation has been noted between them in some cases, the phenomenon itself is not fully understood. Based on the results of our computational study, it can be concluded that the 2D aromatic character of the fused (exo) five-membered ring is low, even in cases where significant conjugation was proposed in previous studies. Moreover, the carborane moiety constricts the bonding properties of the exo ring, thus prohibiting or promoting different Lewis resonance structures. These results will shed further light on the design and electronic modulation of new carborane-based materials.
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