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Updated: Mar 23, 2026

Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Guest-Induced Arylamide Polymer Helicity: Twist-Sense Bias and Solvent-Dependent Helicity Inversion
Peng Zhang1, Liang Zhang1, Ze-Kun Wang1
1Department of Chemistry, Collaborative Innovation Centre of Chemistry for Energy Materials (iChEM), Fudan University, 220 Handan Road, Shanghai, 200433, China.
Abstract:
A benzene/naphthalene alternately incorporated amide polymer was synthesized and characterized. (1) H NMR spectroscopy, fluorescence, and circular dichroism (CD) experiments indicated that, in chloroform, the polymer could be induced by the chiral l-aspartic acid dianion or one of its derivatives to form a helical tubular conformation with twist-sense bias. CD titration studies showed that the l-aspartic acid dianion (8 equiv.) could lead to a maximum Cotton effect. It was also revealed that the twist-sense bias obeyed the majority rule, and 70 % enantiomeric excess could realize the maximum helicity bias. Adding acetonitrile to the solution of chloroform caused inversion of the guest-induced helicity bias of the polymer.
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