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Updated: Jun 28, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Controlled Formation and Unusual Reactivity of Cyanohexatriyne (HC7N), a Synthetically Challenging Interstellar
Léa Lefrançois1, Mano Cremer1, Thierry Roisnel1
1ISCR (Institut Des Sciences Chimiques De Rennes) - UMR6226, Univ Rennes, École Nationale Supérieure de Chimie de Rennes, CNRS, Rennes, F-35000, France.
None:
Cyanohexatriyne (HC7N), a highly unstable member of the interstellar cyanopolyyne family, has long resisted synthetic access. We report the first reproducible formation of HC7N at the milligram scale, enabled by a cobalt-alkyne masking strategy that circumvents the intrinsic instability of extended sp-carbon chains bearing a terminal nitrile. This approach overcomes the limitations of classical Csp-Csp coupling methods and provides enough material for chemical investigation. The formed HC7N was characterized in solution and shown to undergo a rapid and stereoselective conjugate addition with diethylamine to the terminal C≡C triple bond.
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