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Updated: Feb 17, 2026

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Photoswitching Lewis Acid Catalysis with Highly Fatigue Resistant Photochromic Boronates
Lennart Stoess1, Jeremy A Davis1, Lutz Greb1
1Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, Heidelberg 69120, Germany.
Abstract:
Photoswitchable Lewis acids represent an untapped frontier in catalysis. Here, we introduce highly fatigue-resistant diarylethene-functionalized boronates and systematically elucidate how substituent patterns govern their photoswitching ability. These Lewis acids feature large tunable affinity amplitudes suitable for on/off control of diverse Lewis acid catalyses and a Lewis base release transformation. Using the emerging framework of global and effective Lewis acidity (gLA and eLA), we demonstrate how photoisomerization divergently modulates both the thermodynamics of Lewis acid-base association and the activation of bound substrates. Unlike irreversible photo Lewis acid generators, the reversibility of this system further allows the photochemical generation of out-of-equilibrium states. These findings highlight the broad potential of photoswitchable boronates for advanced functional applications.
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