Dynamic axial‐to‐helical communication mechanism in poly[(allenylethynylenephenylene)acetylene]s under external stimuli
DATE:
2023-07-17
UNIVERSAL IDENTIFIER: http://hdl.handle.net/11093/5780
EDITED VERSION: https://doi.org/10.1002/anie.202303329
UNESCO SUBJECT: 2306.16 Esteroquímica y Análisis Conformacional
DOCUMENT TYPE: article
ABSTRACT
Helix inversion in chiral dynamic helical polymers is usually achieved by conformational changes at the pendant groups induced through external stimuli. Herein, a different mechanism of helix inversion in poly(phenylacetylene)s (PPAs) is presented, based on the activation/deactivation of supramolecular interactions. We prepared poly[(allenylethynylenephenylene)acetylene]s (PAEPAs) in which the pendant groups are conformationally locked chiral allenes. Therefore, their substituents are placed in specific spatial orientations. As a result, the screw sense of a PAEPA is fixed by the allenyl substituent with the optimal size/distance relationship to the backbone. This helical sense command can be surpassed by supramolecular interactions between another substituent on the allene and appropriate external stimuli, such as amines. So, a helix inversion occurs through a novel axial‐to‐helical communication mechanism, opening a new scenario for taming the helices of chiral dynamic helical polymers.