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Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Flavylium based dual photochromism: addressing cis-trans isomerization and ring opening-closure by different light
Sandra Gago1, Nuno Basílio, Artur J Moro
1LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal. fp@fct.unl.pt.
Abstract:
The multistate system of 4',7-dihydroxy-3-methoxyflavylium is constituted by a multiequilibrium involving trans-chalcone, cis-chalcone, hemiketal, flavylium cation and quinoidal base. This system possesses two independently addressable inter-connected photochromic systems based on the cis-trans isomerization and ring opening-closure of the hemiketal.
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