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Updated: Aug 16, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Preparation of carbocycles via base-catalyzed endo-mode cyclization of allenes
Chisato Mukai1, Norikazu Kuroda, Rie Ukon
1Division of Pharmaceutical Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. cmukai@kenroku.kanazawa-u.ac.jp
Abstract:
A new and reliable procedure for constructing five- to seven-membered carbocycles via an endo-mode ring-closing reaction of 1-phenylsulfonylallenes with a substituent that has a terminal active methine moiety at the C1-position has been developed. Trisubstituted 1-phenylsulfonylallenes underwent a similar endo-mode ring-closing reaction to produce the corresponding five- to seven-membered carbocycles, while the formation of six- and seven-membered carbocycles from the corresponding tetrasubstituted allene was not realized. In addition, the introduction of an aromatic ring to the alkyl side chain of the starting allenes made possible the construction not only of normal-sized carbocycles but also an eight-membered framework.
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