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Updated: Jun 12, 2025

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes

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Published on: November 21, 2017

Directional Ring Translocation in a pH- and Redox-Driven Tristable [2]Rotaxane.

Leonardo Andreoni^1,2, Jessica Groppi^2,3, Özlem Seven^2,3

¹Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, viale del Risorgimento 4, 40136, Bologna, Italy.

Angewandte Chemie (International Ed. in English)

|September 20, 2024

Summary

Researchers developed a novel rotaxane molecule with three recognition sites. Its macrocycle can be precisely controlled along the axle using orthogonal stimuli, paving the way for molecular machines.

Keywords:

Ammonium Bypiridinium Crown ethers Molecular Machines Rotaxanes Triazolium

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Photogeneration of N-Heterocyclic Carbenes: Application in Photoinduced Ring-Opening Metathesis Polymerization

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Published on: November 29, 2018

Area of Science:

Supramolecular Chemistry
Molecular Machines

Background:

Rotaxanes are molecular architectures with a macrocycle threaded onto an axle.
Controlling the movement of the macrocycle on the axle is key for developing molecular machines.

Purpose of the Study:

To synthesize and characterize a novel [2]rotaxane with multiple recognition sites.
To investigate the orthogonal stimuli-responsive behavior for precise macrocycle translation.

Main Methods:

Synthesis of a [2]rotaxane featuring a dibenzo-24-crown-8 macrocycle and a functionalized axle.
Characterization using spectroscopic and analytical techniques.
Thermodynamic analysis to understand the operational mechanisms.

Main Results:

Successful synthesis and characterization of the target [2]rotaxane.
Demonstrated orthogonal stimuli-responsive translation of the macrocycle along the axle using pH and electrochemical inputs.
Detailed thermodynamic data provided insights into the system's operation.

Conclusions:

The developed rotaxane exhibits tristable behavior controlled by orthogonal stimuli.
This work provides a foundation for creating advanced molecular linear motors.
The system holds potential for the development of sophisticated molecular logic gates.