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Updated: Jul 29, 2025

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Helicity induction and memory of a lipophilic Brønsted acid-type poly(phenylacetylene) in non-polar solvents
Yuki Nishikawa1, Daisuke Hirose2, Shota Sona1
1Graduate School of Frontier Science Initiative, Kanazawa University, Kakuma-machi, Kanazawa, 920-1192, Japan.
Abstract:
A novel lipophilic Brønsted acid-type PPA (poly-1-H) bearing a sulfonylphosphoramidic acid moiety, covered with a dynamically axially chiral biphenyl pendant, was synthesized and found to form a preferred-handed helical conformation in non-polar solvents upon complexation with non-racemic amines. This induced helicity was maintained after replacement with achiral amines ("dynamic helicity memory"). In addition, poly-1-H exhibited "static helicity memory" in which the induced helical conformation was maintained in non-polar solvents, even after acidification with a stronger acid without replacement with achiral amines.
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