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Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
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Macroscopic Helical Assembly of One-Dimensional Coordination Polymers: Helicity Inversion Triggered by Solvent
Jia-Ge Jia1,2, Chen-Chen Zhao3, Yi-Fan Wei1
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210023, P. R. China.
Journal of the American Chemical Society
|October 27, 2023
Summary
This study demonstrates using solvents to control the helical structure of chiral coordination polymers (CPs). Different solvents induce various morphologies, including superhelices with tunable chirality, offering new possibilities for chiral material design.
Area of Science:
- Coordination Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Assembling macroscopic helices with controllable chirality in artificial systems is challenging.
- Chiral coordination polymers (CPs) offer potential for creating complex helical structures.
- Understanding the formation mechanisms of chiral self-assemblies is crucial for design.
Purpose of the Study:
- To utilize solvents as a tool to induce and control the formation of macroscopic helices in chiral coordination polymers.
- To investigate the influence of solvent composition on the morphology and helical sense of self-assembled CPs.
- To explore the potential of these chiral helical CPs in applications like chiral recognition.
Main Methods:
- Synthesis of chiral coordination polymers using a Ni/R-,S-BrpempH2 system.
- Systematic variation of solvent mixtures (water with acetonitrile, methanol, ethanol, or propanol isomers) to control self-assembly.
- Characterization of the resulting morphologies using microscopy and structural analysis.
- Theoretical calculations to rationalize the observed helical structures.
- Adsorption studies to evaluate chiral recognition capabilities.
Main Results:
- Solvent-dependent formation of diverse morphologies: twisted ribbons, needle-like crystals, nanofibers, and superhelices.
- Successful induction of macroscopic helices in chiral coordination polymers by tuning solvent composition.
- Control over the helical sense (left-handed or right-handed) of superhelices by using different propanol isomers (NPA vs. IPA).
- Demonstration of chiral recognition behavior in the synthesized helical CPs.
Conclusions:
- Solvents are effective tools for directing the self-assembly of chiral coordination polymers into macroscopic helical structures.
- The helical sense of the self-assembled structures can be precisely controlled by solvent choice, particularly using isomers.
- This approach provides a pathway for developing novel chiral materials with tunable helical morphologies and potential functionalities.
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