Tuning the Photoisomerization Mechanism of Oxindole Switches with Electron-Donating Substituents
Year: 2025
Type: article
Abstract: This study investigates the photoreaction mechanism of a hydroxy-substituted oxindole photoswitch using femtosecond transient absorption, fluorescence up-conversion, and computational chemistry. Deprotonation of the hydroxyl group enhances the push-pull character in the molecule, allowing tuning of the photoisomerization mechanism from a precessional to an axial motion. The neutral form of the switch exhibits longer excited-state lifetimes, while the anionic form decays rapidly within 200 fs. Computational models show that deprotonation increases the charge transfer and accessibility to conical intersections. This work highlights how varying the electron-donating strength of a substituent in a push-pull photoswitch tunes the photoreaction mechanism in designing photoswitches.
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
Funders: Göran Gustafssons Stiftelser, Agence Nationale de la Recherche, Institut National de la Santé et de la Recherche Médicale, Rijksuniversiteit Groningen, National Science Council, Ministerie van Onderwijs, Cultuur en Wetenschap, Université de Strasbourg, Vetenskapsrådet, Stiftelsen Lars Hiertas Minne, Centre National de la Recherche Scientifique, Uppsala Universitet, Laboratoires d'excellence Nanostructures en Interaction avec leur Environnement, Zernike Institute for Advanced Materials, Rijksuniversiteit Groningen
Awards: Synthesis and development of novel photoactuators and photoreactions by computer-aided design, G1949054838, Par-delà les frontières, l'Université de Strasbourg, G2255650664, G2448992187, G2694206344, G2729097322, Façonner les talents en formation et en recherche à l'Université de Strasbourg, G3357951378, G3531901323, G4779185514, Unravelling the photoisomerization mechanism via environment–induced tuning of reactivity, G5348650765, G6136357505, G6276897512, G7569742080, G783677704, Nanostructures en Interaction avec leur Environnement, NAISS, G894966930
OpenAlex ID: W4409244160