Shedding Light on the Photoisomerization Pathway of Donor–Acceptor Stenhouse Adducts

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61989592%3A15310%2F17%3A73584446" target="_blank" >RIV/61989592:15310/17:73584446 - isvavai.cz</a>

Výsledek na webu

<a href="http://pubs.acs.org/doi/10.1021/jacs.7b09081" target="_blank" >http://pubs.acs.org/doi/10.1021/jacs.7b09081</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1021/jacs.7b09081" target="_blank" >10.1021/jacs.7b09081</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Shedding Light on the Photoisomerization Pathway of Donor–Acceptor Stenhouse Adducts

Popis výsledku v původním jazyce

Donor-acceptor Stenhouse adducts (DASAs) are negative photochromes that hold great promise for a variety of applications. Key to optimizing their switching properties is a detailed understanding of the photoswitching mechanism, which, as yet, is absent. Here we characterize the actinic step of DASA-photoswitching and its key intermediate, which was studied using a combination of ultrafast visible and IR pump-probe spectroscopies and TD-DFT calculations. Comparison of the time-resolved IR spectra with DFT computations allowed to unambiguously identify the structure of the intermediate, confirming that light absorption induces a sequential reaction path in which a Z-E photoisomerization of C-2-C-3 is followed by a rotation around C-3-C-4 and a subsequent thermal cyclization step. First and second-generation DASAs share a common photoisomerization mechanism in chlorinated solvents with notable differences in kinetics and lifetimes of the excited states. The photogenerated intermediate of the second-generation DASA was photo-accumulated at low temperature and probed with time-resolved spectroscopy, demonstrating the photoreversibility of the isomerization process. Taken together, these results provide a detailed picture of the DASA isomerization pathway on a molecular level.

Název v anglickém jazyce

Shedding Light on the Photoisomerization Pathway of Donor–Acceptor Stenhouse Adducts

Popis výsledku anglicky

Donor-acceptor Stenhouse adducts (DASAs) are negative photochromes that hold great promise for a variety of applications. Key to optimizing their switching properties is a detailed understanding of the photoswitching mechanism, which, as yet, is absent. Here we characterize the actinic step of DASA-photoswitching and its key intermediate, which was studied using a combination of ultrafast visible and IR pump-probe spectroscopies and TD-DFT calculations. Comparison of the time-resolved IR spectra with DFT computations allowed to unambiguously identify the structure of the intermediate, confirming that light absorption induces a sequential reaction path in which a Z-E photoisomerization of C-2-C-3 is followed by a rotation around C-3-C-4 and a subsequent thermal cyclization step. First and second-generation DASAs share a common photoisomerization mechanism in chlorinated solvents with notable differences in kinetics and lifetimes of the excited states. The photogenerated intermediate of the second-generation DASA was photo-accumulated at low temperature and probed with time-resolved spectroscopy, demonstrating the photoreversibility of the isomerization process. Taken together, these results provide a detailed picture of the DASA isomerization pathway on a molecular level.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10403 - Physical chemistry

Projekt

<a href="/cs/project/LO1305" target="_blank" >LO1305: Rozvoj centra pokročilých technologií a materiálů</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2017

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Journal of the American Chemical Society

ISSN

0002-7863

e-ISSN

—

Svazek periodika

139

Číslo periodika v rámci svazku

44

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

4

Strana od-do

15596-15599

Kód UT WoS článku

000415028200011

EID výsledku v databázi Scopus

2-s2.0-85033229419