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Updated: Apr 14, 2026

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Cumulene rotaxanes: stabilization and study of [9]cumulenes
Michael Franz1, Johanna A Januszewski1, Dominik Wendinger1
1Department of Chemistry and Pharmacy & Interdisciplinary Center of Molecular Materials (ICMM), University of Erlangen-Nuremberg (FAU), Henkestrasse 42, 91054 Erlangen (Germany) http://www.chemie.uni-erlangen.de/tykwinski.
Abstract:
The stabilization of long [n]cumulenes has traditionally been achieved by placing sterically bulky "protecting groups" at the termini, which shield the reactive carbon chain from unwanted reactions. Herein, we present an alternative strategy: stabilization through threading the sp-hybridized carbon chain through a phenanthroline-based macrocycle. The result is stable [9]cumulene rotaxanes that enable the study of properties as a function of length for [n]cumulenes in unprecedented detail, including by quantitative UV/Vis spectroscopy, cyclic voltammetry, and differential scanning calorimetry. The experimental results are supported by DFT calculations.
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