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Updated: Jun 12, 2025

Controlled Photoredox Ring-Opening Polymerization of O-Carboxyanhydrides Mediated by Ni/Zn Complexes
Published on: November 21, 2017
Directional Ring Translocation in a pH- and Redox-Driven Tristable [2]Rotaxane
Leonardo Andreoni1,2, Jessica Groppi2,3, Özlem Seven2,3
1Dipartimento di Chimica Industriale "Toso Montanari", Università di Bologna, viale del Risorgimento 4, 40136, Bologna, Italy.
Abstract:
We describe the synthesis and characterization of a [2]rotaxane comprising a dibenzo-24-crown-8 (DB24C8) macrocyclic component and a thread containing three recognition sites: ammonium (AmH+), bipyridinium (Bpy2+) and triazolium (Trz+). AmH+ and Bpy2+ are responsive to fully orthogonal stimuli, pH and electrochemical, which allows to precisely control the directional translation of the macrocycle along the axle. A better understanding of the processes driving the operation of the system was obtained thanks to an in-depth thermodynamic characterization. Orthogonal stimuli responsive tristable rotaxanes represent the starting point for the creation of linear motors and the development of molecular logic gates.
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