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Library of Stereoregular Polythioesters for Stereocomplex Formation Enabled by Isomerization-Driven Cationic
Pengjun Yuan1,2, Yongliang Xia2, Xi Zhang2
1Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering, College of Chemistry, and Molecular Engineering, East China University of Science and Technology, Shanghai, 200237, China.
Angewandte Chemie (International Ed. in English)
|June 3, 2025
Summary
Researchers developed stereoregular polythioesters from chiral thionolactones using metal-free initiators. This breakthrough enables new sulfur-containing polymer stereocomplexes with high melting points, advancing sustainable polymer science.
Area of Science:
- Polymer Chemistry
- Sustainable Polymers
- Supramolecular Chemistry
Background:
- Supramolecular stereocomplexation is key for sustainable polymers, with oxygen-containing polymers being well-studied.
- Sulfur-containing polymers, a new class of sustainable materials, are underexplored due to challenges in synthesizing stereoregular polymers and low supramolecular interactions.
Purpose of the Study:
- To overcome challenges in synthesizing stereoregular sulfur-containing polymers.
- To explore supramolecular stereocomplexation in polythioesters.
- To develop new sustainable polymers with enhanced properties.
Main Methods:
- Utilized a metal-free cationic initiator, [Et3O]+[B(C6F5)4]-, for controlled isomerization-driven ring-opening polymerizations (IROPs).
- Investigated nine examples of chiral five-membered thionolactones.
- Employed a unique monomer-stabilized SN2 propagation mechanism to control stereoregularity and minimize racemization.
Main Results:
- Achieved controlled IROPs of chiral thionolactones, yielding stereoregular polythioesters with high isotacticities (80.0%-99.5%).
- Disclosed two new polythioester stereocomplexes exhibiting high melting temperatures (117.0-161.0 °C).
- Revealed fundamental aspects of stereocomplex formation mechanisms and critical factors influencing stereocomplexation ability.
Conclusions:
- Established a novel method for synthesizing stereoregular polythioesters, enabling access to a new class of sustainable polymers.
- Demonstrated the formation of high-melting polythioester stereocomplexes, expanding the scope of supramolecular polymer applications.
- Provided crucial insights into the structure-stereocomplexation relationships and factors governing stereocomplex formation in polythioesters.
Keywords:
PolythioestersRing‐opening polymerizationStereoregular polymerSupramolecular stereocomplexationSustainable polymersMore Related Videos
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