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Updated: Jun 23, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Catalytic 2,3,4-hexatriene formation by terminal alkyne coupling at calcium
Anthony G M Barrett1, Mark R Crimmin, Michael S Hill
1Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London, UK.
Abstract:
Heteroleptic calcium amides effect the catalytic dimerisation of the terminal alkyne CH(3)OCH(2)C[triple bond, length as m-dash]CH to the hexatriene (CH(3)OCH(2))CH[double bond, length as m-dash]C[double bond, length as m-dash]C[double bond, length as m-dash]CH(CH(2)OCH(3)) under mild conditions; the reaction is proposed to occur via a dimeric calcium acetylide intermediate and to be promoted by polarisation of the electron density within the alkynide C[triple bond, length as m-dash]C bonds.
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