Mechanistic Basis for Red Light Switching of Azonium Ions
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989100%3A27740%2F23%3A10254101" target="_blank" >RIV/61989100:27740/23:10254101 - isvavai.cz</a>
Alternative codes found
RIV/61989592:15640/23:73621898
Result on the web
<a href="https://pubs.acs.org/doi/10.1021/jacs.3c06157" target="_blank" >https://pubs.acs.org/doi/10.1021/jacs.3c06157</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1021/jacs.3c06157" target="_blank" >10.1021/jacs.3c06157</a>
Alternative languages
Result language
angličtina
Original language name
Mechanistic Basis for Red Light Switching of Azonium Ions
Original language description
Azonium ions formed by the protonation of tetra-ortho-methoxy-substituted aminoazobenzenes photoisomerize with red light under physiological conditions. This property makes them attractive as molecular tools for the photocontrol of physiological processes, for example, in photopharmacology. However, a mechanistic understanding of the photoisomerization process and subsequent thermal relaxation is necessary for the rational application of these compounds as well as for guiding the design of derivatives with improved properties. Using a combination of sub-ps/ns transient absorption measurements and quantum chemical calculations, we show that the absorption of a photon by the protonated E-H+ form of the photoswitch causes rapid (ps) isomerization to the protonated Z-H+ form, which can also absorb red light. Proton transfer to solvent then occurs on a microsecond time scale, leading to an equilibrium between Z and Z-H+ species, the position of which depends on the solution pH. Whereas thermal isomerization of the neutral Z form to the neutral E form is slow (similar to 0.001 s(-1)), thermal isomerization of Z-H+ to E-H+ is rapid (similar to 100 s(-1)), so the solution pH also governs the rate at which E/E-H+ concentrations are restored after a light pulse. This analysis provides the first complete mechanistic picture that explains the observed intricate photoswitching behavior of azonium ions at a range of pH values. It further suggests features of azonium ions that could be targeted for improvement to enhance the applicability of these compounds for the photocontrol of biomolecules.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10400 - Chemical sciences
Result continuities
Project
—
Continuities
—
Others
Publication year
2023
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Journal of the American Chemical Society
ISSN
0002-7863
e-ISSN
1520-5126
Volume of the periodical
145
Issue of the periodical within the volume
36
Country of publishing house
US - UNITED STATES
Number of pages
9
Pages from-to
19894-19902
UT code for WoS article
001061672500001
EID of the result in the Scopus database
2-s2.0-85171203333