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Updated: Jan 18, 2026

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Deaminative Ring Contraction for the Modular Synthesis of Pyrido[n]helicenes
Zachary T Schwartz1, Chelsea D Valiton1, Myles A Lovasz1
1Department of Chemistry, The University of Utah, Salt Lake City, Utah 84112, United States of America.
None:
A modular strategy involving tertiary amines as templates to build multiple carbon-carbon bonds via reductive cyclization and deaminative contraction steps enables the scalable synthesis of (di)aza[5]helicenes and (di)aza[6]helicenes. The methods permit the rapid and gram-scale assembly of key pyridyl-containing dihydroazepines that are advanced using a developed deaminative contraction to access the N-atom positional isomers of pyrido[5] and [6]helicenes. A telescoped synthesis demonstrates expedited access to (±)-1-aza[6]helicene, a resolvable helicene valued for its circularly polarized luminescence properties.
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