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Updated: Dec 30, 2025

Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Linear and Third-Order Nonlinear Optical Properties of Triazobenzene-1,3,5-triazinane-2,4,6-trione (Isocyanurate)
Ziemowit Pokladek1,2, Marta Dudek1,2, Olivier Mongin3
1Department of Bioorganic Chemistry, Wroclaw University of Science and Technology, 50-370, Wroclaw, Poland.
Abstract:
The synthesis of three new isocyanurate derivatives 2-X (X=NO2 , H, NMe2 ) with azobenzene arms terminated by various X substituents is reported, and their linear and nonlinear absorption properties are studied. It is shown that mixtures that contain increased contents of cis-azo isomers can be reversibly generated upon photoirradiation at specific wavelengths from the most stable all-trans isomers with X=NO2 and H. In addition, we show that 2-X derivatives are two-photon absorbers with cross-section maxima around 120 GM for 2-NO2 , thus indicating that trans-to-cis isomerization might be achievable by two-photon excitation, whereas the photoinduced structural changes should have only a modest influence on these nonlinear absorption properties.
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