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Published on: September 26, 2016
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Consequences of hidden kinetic pathways on supramolecular polymerization
Jonas Matern1, Kalathil K Kartha1, Luis Sánchez2
1Organisch-Chemisches Institut , Westfälische Wilhelms-Universität Münster , Corrensstraße 36 , 48149 Münster , Germany .
Chemical Science
|September 3, 2020
Summary
Hidden kinetic pathways in supramolecular polymerization can override thermodynamic control. A chiral Pd(II) complex demonstrated that a "hidden" pathway forms a stable kinetic aggregate, preventing relaxation to the thermodynamic minimum.
Area of Science:
- Supramolecular chemistry
- Polymer science
- Chemical kinetics
Background:
- Supramolecular polymerization involves competition between kinetic and thermodynamic processes.
- Identifying kinetic pathways can be challenging, complicating self-assembly analysis.
Purpose of the Study:
- To demonstrate the significant impact of "hidden" kinetic pathways on supramolecular polymerization.
- To analyze how kinetic aggregates can overrule thermodynamic implications.
Main Methods:
- Detailed analysis of the supramolecular polymerization of a chiral Palladium(II) complex.
- Investigation of competing aggregate formation (Agg I and Agg II).
- Characterization of a "hidden" pathway leading to kinetic aggregate Agg II.
Main Results:
- A "hidden" pathway, inaccessible via thermal protocols, forms kinetic aggregate Agg II.
- Agg II formation involves a cooperative process followed by rapid kinetics-driven superstructure formation.
- Agg II exhibits remarkable kinetic stability (>6 months), suppressing thermodynamic aggregate nucleation.
- Fast kinetics of cluster formation sequestered monomers, preventing relaxation to the thermodynamic minimum.
Conclusions:
- "Hidden" kinetic pathways can profoundly influence and even dominate supramolecular polymerization outcomes.
- Kinetic aggregates formed via hidden pathways can exhibit exceptional stability and control self-assembly.
- Understanding these hidden pathways is crucial for controlling supramolecular polymerization processes.
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