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Updated: May 27, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Allylic substitution on cyclopentene and -hexene rings with alkynylcopper reagents
1Department of Biomolecular Engineering, Tokyo Institute of Technology, Box B52, Nagatsuta-cho 4259, Midori-ku, Yokohama 226-8501, Japan.
Abstract:
Substitution of cyclic allylic picolinates with a reagent derived from TMS-C≡CMgBr and a copper salt was investigated. Although the previous type of reagent (TMSC≡CMgBr and CuBr·Me(2)S) developed for linear allylic picolinates was less product selective and regioselective, the Cu(acac)(2)-derived reagent was highly selective (94-95%) to afford the S(N)2' product in good yields. As an application, several C-C bond formations at the acetylenic carbon and the synthesis of the PG intermediate were studied with success.
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