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Updated: Jul 2, 2026
Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
A kinetic study of guest displacement reactions on a host-guest complex with a photoswitchable calixarene
Matthias C Letzel1, Christian Schäfer, Francesca R Novara
1Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld, Germany.
Abstract:
The displacement processes of several guests, incorporated in a calixarene host system, were investigated in the gas phase by electrospray ionization-Fourier transform-ion cyclotron resonance (ESI-FT-ICR) mass spectrometry. The complexes resulting from a resorcin[4]arene host with ammonia and sec-butylamine guests were isolated in an ICR-cell, separately using both states of the photoswitch as well as two reference systems for the open and closed forms of the photoswitchable host. The isolated complexes were forced to exchange the guest by using methylamine, ethylamine and sec-butylamine, resulting in different reaction rates for all the measured systems. Especially, the reaction rates of both states of the photoswitch are dependent on the provided guest. Potential side effects like proton exchanges were examined by an H/D-exchange experiment. The results were investigated and supported by quantum chemical calculations (DFT).
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