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Reversible adaptation to photoinduced shape switching by oligomer-macrocycle interconversion with component selection
Ghislaine Vantomme1, Jean-Marie Lehn
1Laboratoire de Chimie Supramoléculaire, ISIS, Université de Strasbourg, 8 Allée Gaspard Monge, 67000 Strasbourg (France).
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 10, 2014
Summary
Molecular photoswitch 1 undergoes shape changes with light or metal ions, altering its reactions with diamines. This leads to selective formation of different molecular structures, demonstrating constitutional adaptation.
Area of Science:
- Supramolecular Chemistry
- Dynamic Covalent Chemistry
- Molecular Switches
Background:
- Molecular photoswitches can alter their shape and reactivity upon external stimuli.
- Dynamic covalent chemistry allows for the formation and rearrangement of molecular structures.
- Self-assembly processes can lead to the formation of complex architectures like macrocycles.
Purpose of the Study:
- To investigate the constitutional adaptation of a molecular photoswitch system in response to light and metal cations.
- To explore the selective incorporation of different diamine components into dynamic covalent structures.
- To demonstrate a triple state system with distinct selection mechanisms.
Main Methods:
- Photoisomerization of molecular photoswitch 1 (E/Z configurations).
- Dynamic covalent reactions between the photoswitch and various linear diamines.
- Investigation of macrocycle and oligomer formation under different conditions (light, metal ions).
Main Results:
- Photoinduced E/Z switching of photoswitch 1 drives interconversion between non-cyclic oligomers and macrocycles.
- In the presence of light, selective formation of a macrocycle with H2N(CH2)7NH2 is observed.
- Metal cations induce selective macrocycle formation with H2NCH2CH2OCH2CH2NH2 via coordination.
- The system exhibits no selection, photoselection, or metalloselection depending on the stimulus.
Conclusions:
- Constitutional adaptation occurs in a triple state system involving oligomers and two types of macrocycles.
- Light and metal cations act as orthogonal stimuli to control molecular structure formation.
- The study highlights tunable selectivity in dynamic covalent systems based on external triggers.
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