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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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Stimuli Induced Reversible Switching Between a Self-Assembled 2-Catenane and the Constituent Coordination Rings
Raveena Soni1, Devjanee Bardhan1, Shobhana Krishnaswamy1
1IoE Center of Molecular Architecture, Department of Chemistry, Indian Institute of Technology Madras, Chennai, 600036, India.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|November 25, 2024
Summary
Researchers developed a new method to create interlocked molecular rings called catenanes. This approach uses anion binding to reversibly switch between catenanes and their individual ring components, paving the way for novel molecular machines.
Area of Science:
- Supramolecular Chemistry
- Coordination Chemistry
- Materials Science
Background:
- Catenanes are mechanically interlocked molecular architectures with unique properties.
- Controlling the assembly and disassembly of catenanes is crucial for developing molecular machines.
Purpose of the Study:
- To design and synthesize novel catenane structures using readily available ligands and metal ions.
- To investigate the role of guest molecules in the formation and disassembly of catenanes.
- To establish a principle for reversible switching between catenanes and their constituent rings.
Main Methods:
- One-pot synthesis of octa-cationic 2-catenane using cis-Pd(tmeda)2+, C-shaped ligand L1, and linear ligand L3.
- Formation of a guest-bound coordination ring in the presence of a di-anionic guest.
- Complexation with C-shaped ligand L22+ and L3 to form a hexa-cationic macromonocyclic ring.
- Demonstration of guest-induced ring separation and subsequent reversion to the catenane structure.
Main Results:
- Successfully synthesized an octa-cationic 2-catenane and a hexa-cationic macromonocyclic ring.
- Showcased guest-induced separation of the catenane into its constituent rings.
- Demonstrated the reversibility of the process by sequestering the guest molecule.
- Established anion-binding and sequestering as a core concept for reversible switching.
Conclusions:
- A novel design principle for reversible switching between catenanes and macromonocyclic rings has been established.
- Anion-binding and sequestering offer a versatile strategy for controlling supramolecular assembly.
- This work provides a foundation for the development of responsive molecular materials and machines.
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