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Updated: Aug 17, 2026

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
[Nickel-catalyzed [2 + 2 + 2] cocyclization and its application to the synthetic organic chemistry]
1Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
Abstract:
A nickel (0)-catalyzed asymmetric [2 + 2 + 2] cocyclization has been realized for the first time. This reaction involves conceptually new enantiotopic group selective formation of a nickelacyclopentadiene intermediate and produces an isoindoline derivative (73% ee, 78% conv. yield) and an isoquinoline derivative (54% ee, 62% yield) having benzylic chiral carbon centers. The synthesizing methods of biaryls using the nickel-catalyzed [2 + 2 + 2] cocyclization were also developed. Two ways for the synthesis of biaryl using [2 + 2 + 2] cocyclization were investigated: one method is that biaryls synthesized from alkyne having a phenyl group and 2 equivalents of acetylene, and the other method is that those were synthesized from alpha,omega-diyne having a phenyl group at the alpha-position and acetylene.
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