Synthesis, photophysics and two-photon absorption of imidazole-centred tripodal chromophores

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216275%3A25310%2F24%3A39921720" target="_blank" >RIV/00216275:25310/24:39921720 - isvavai.cz</a>

Result on the web

<a href="https://pubs.rsc.org/en/content/articlelanding/2024/cp/d4cp02227k" target="_blank" >https://pubs.rsc.org/en/content/articlelanding/2024/cp/d4cp02227k</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1039/d4cp02227k" target="_blank" >10.1039/d4cp02227k</a>

Result language

angličtina

Original language name

Synthesis, photophysics and two-photon absorption of imidazole-centred tripodal chromophores

Original language description

Tripodal push-pull chromophores with D-(pi-A)3 arrangement were synthesized using 1-methyl-2,4,5-triphenyl-1H-imidazole as a central electron donor, and their thermal, electrochemical, photophysical and non-linear optical properties were studied and corroborated with quantum-chemical calculations. Their facile synthesis involved Suzuki-Miyaura and Knoevenagel reactions, allowing the installation of various peripheral electron acceptors such as formyl, cyano, ester, trifluoromethyl and more complex moieties such as malonic/acetic acid derivatives, indan-1,3-dione and rhodanine. All phenyl rings appended at the central imidazole core were more or less twisted depending on the peripheral substitution. Although imidazole undergoes reversible one-electron oxidation, peripheral acceptors are reduced irreversibly in a multi-electron process. This behaviour is further seen as a variation of the LUMO, while the HOMO remained almost unaltered across the whole series. TD-DFT calculations revealed centrifugal charge transfer from the central imidazole to all C2, C4 and C5 branches occupied by the LUMO, LUMO+1 and LUMO+2. The HOMO-LUMO gap is tuneable within the range of 3.55-2.31 eV, while the longest-wavelength absorption/emission maxima were found within the broad range of 304-448/393-612 nm. Although the absorption spectra are solvent-independent, the emission depends strongly on the solvent polarity and the electron-withdrawing power of the peripheral acceptors. Extended chromophores with complex electron acceptors were investigated as two-photon absorbers, revealing relatively good cross-section values of up to 521 GM and a figure-of-merit (Phi F x delta 2PA) of around 190 GM. Tripodal imidazole-centred chromophores bearing peripheral acceptors were prepared and investigated. The observed centrifugal ICT results in tuneable (nonlinear) optical properties and two-photon absorption cross-sections of up to 521 GM.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10401 - Organic chemistry

Project

—

Continuities

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Publication year

2024

Confidentiality

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

Name of the periodical

Physical Chemistry Chemical Physics

ISSN

1463-9076

e-ISSN

1463-9084

Volume of the periodical

26

Issue of the periodical within the volume

31

Country of publishing house

GB - UNITED KINGDOM

Number of pages

11

Pages from-to

20908-20918

UT code for WoS article

001274988000001

EID of the result in the Scopus database

2-s2.0-85199717213