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Updated: May 17, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Synthesis and structural elucidation of diversely functionalized 5,10-diaza[5]helicenes
Deepali Waghray1, Jing Zhang, Jeroen Jacobs
1Molecular Design and Synthesis, Department of Chemistry, Katholieke Universiteit Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium.
Abstract:
Diversely functionalized diaza[5]helicenes have been synthesized starting from 6,9-dichloro-5,10-diaza[5]helicene, which was prepared from a readily available quinoline building block via Wittig reaction followed by photochemical electrocyclization. The helicene skeleton was substituted by a variety of O-, S-, N-, and C-centered nucleophiles using nucleophilic aromatic substitution reactions and palladium-catalyzed reactions like Suzuki coupling and Buchwald-Hartwig aminations. We have determined, using X-ray single-crystal diffraction, the crystal structures of the chloro- and methoxy-substituted diaza[5]helicenes. A resolution strategy based on diastereomeric separation by substitution of the dichloro derivative with a chiral amine has been shown.
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