Related Experiment Video
Updated: Jan 14, 2026
06:24
High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
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Azobenzene-Based Glycomacrocycles: Synthesis, Photoisomerization, and Photomodulation of Liquid Crystal Helical Pitch
Gaoyu Li1, Reo Hatano2, Stéphane Maisonneuve1
1PPSM, Université Paris-Saclay, ENS Paris-Saclay, CNRS, Gif-sur-Yvette, 91190, France.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|October 24, 2025
Summary
Novel chiral glycomacrolactones were synthesized and applied as dopants in liquid crystals. These compounds exhibit photochromic properties and can control liquid crystal helix structure, with some achieving photoinduced helix inversion.
Area of Science:
- Organic Chemistry
- Materials Science
- Photochemistry
Background:
- Azobenzene derivatives are known for their photochromic properties.
- Chiral dopants are crucial for controlling the helical structure of cholesteric liquid crystals (CLCs).
- Glycomacrolactones offer a unique scaffold for developing functional organic materials.
Purpose of the Study:
- To synthesize novel azobenzene-embedded glycomacrolactones.
- To investigate their photochromic and chiroptical properties.
- To explore their application as chiral dopants for photomodulating nematic liquid crystals (NLCs).
Main Methods:
- Synthesis and characterization of glycomacrolactones using NMR, UV/vis, and circular dichroism (CD) spectroscopy.
- Application of synthesized compounds as chiral dopants in NLCs.
- Photomodulation studies to observe changes in helical structure upon UV/vis irradiation.
Main Results:
- All synthesized macrocycles showed good photochromic properties, fatigue resistance, and thermal bistability.
- An amplification of helix and enforcement of helical twisting power (HTP) were observed upon E to Z photoisomerization in NLCs.
- Two glycomacrocycles demonstrated photoinduced helix inversion, a novel finding for this class of compounds.
Conclusions:
- Sugar-ring functionalization critically influences chirality transfer and photoswitching in CLCs.
- The synthesized glycomacrolactones are effective chiral dopants for photomodulating liquid crystal properties.
- This work presents the first example of photoinduced helix inversion in azobenzene-embedded glycomacrolactones for CLC applications.
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