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Updated: Jun 13, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Scorpion-Shaped Hybrid Double Helicenes via Orthogonal Alkyne Annulation Reactions
Mengyu Yao1, Yaru Jing2, Hongyan Bi1
1Chang-Kung Chuang Institute, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200241, China.
Abstract:
Scorpion-shaped hybrid double helicenes, consisting of a [5] or [6] carbohelicene and an aza[4]helicene, have been successfully constructed by orthogonal alkyne annulations via an aryl C-I bond and amido N-H bond from polyaromatic ring-fused iodoisocoumarins. In spite of the unexpected instability upon aerobic oxidation upon ambient visible light irradiation over several days, both ultraviolet-visible absorption and photoluminescence spectra along with density functional theory calculations of these helicenes have been studied, which rely heavily on the bent polyaromatic ring-fused quinolizinone conjugate skeleton. In addition, the Stokes shifts of hybrid double helicenes are generally larger than those of the structurally similar mono-carbohelicenes.
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