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Updated: Jun 16, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
[14]Annulene: cis/trans isomerization via two-twist and nondegenerate planar bond shifting and Möbius conformational
Tobechi Okoronkwo1, Phuong T Nguyen, Claire Castro
1Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, USA.
Abstract:
Mechanisms linking dihydrooctalenes and the corresponding [14]annulene isomers have been investigated computationally. CCSD(T)/cc-pVDZ//BHLYP/6-31G* calculations suggest that the cis/trans isomerization steps required by these mechanisms can occur with reasonable activation barriers by pi-bond shifting, in some cases with two-twist topology, and in others in a planar but nondegenerate fashion. In addition, numerous Mobius conformational minima were located for [14]annulene isomers directly related to the mechanisms studied.
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