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Updated: Jul 9, 2025

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Structural tuning of β-enamino diketones: exploration of solution and crystalline state photochromism
Kiran B Manjappa1, Sheng-Chieh Fan2, Ding-Yah Yang1,2
1Graduate Program for Biomedical and Materials Science, Tunghai University, Taichung, Taiwan.
Abstract:
A library of β-enamino diketones was prepared via base-mediated, three-component reaction of 4-hydroxycoumarins with various aromatic/aliphatic amines and β-nitrostyrenes under microwave irradiation conditions to investigate their photochemical properties. Among the prepared compounds, a thiophene derived β-enamino diketone was found to be light-sensitive and to exhibit unique photochromic behavior, that is, positive photochromism in solution and negative photochromism in crystalline phase. In addition, this prepared photochromic compound was further covalently linked to a structure-related, piezochromic β-enamino diketone moiety to explore its potential multi-stimuli responsive properties.
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