Naslov
Theoretical insights into quinone methides formed from p-cresols

Autori
Šekutor, Marina ; Ma, Jiani ; Škalamera, Đani ; Phillips, David Lee ; Basarić, Nikola

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
27th PhotoIUPAC / International Symposium on Photochemistry / - Dublin, 2018, P165-P165

Skup
27th PhotoIUPAC / International Symposium on Photochemistry

Mjesto i datum
Dublin, Irska, 08.07.2018. - 13.07.2018

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Quinone methides (QMs), TD-DFT, UV-Vis spectra prediction

Sažetak
Quinone methides (QMs) are conjugated reactive intermediates with possible application in biological systems, mainly as alkylating agents for DNA cross-linking [1, 2]. QMs can be generated from phenols both thermally and photochemically and one common photochemical method to generate QMs in biological systems is photodeamination from the corresponding Mannich salts [3, 4]. Once generated from phenol precursors, QMs show both electrophilic and nucleophilic reactivity, making them a valuable tool in biomedicine since they readily react with biologically important molecules. Despite a recurring interest in QMs and numerous studies of their reactivity with different substrates [5], little is still known about the mechanism of photochemical formation of even the simplest derivatives. As part of our ongoing investigation of QMs [1, 4, 6], we undertook a computational study of photochemical deamination of a p-cresol Mannich salt into the corresponding QM. The reaction pathway of QM formation was studied using TD- DFT by applying the PCM/B3LYP/6-311++G(d, p) level of theory with water as a solvent. It is known that obtaining accurate vertical excitation energies can be challenging [7], but we previously tested different DFT functionals for this type of compounds [6] and therefore applied the same approach for the p-cresol derivative. The predicted UV-Vis spectra were in good agreement with the spectra obtained experimentally. We found stationary points for the first excited state, compared them with the ground state molecular geometries, made the corresponding energetic profile of the reaction, and consequently, we propose a mechanism of photodeamination and QM formation.

Izvorni jezik
Engleski

Znanstvena područja
Kemija

POVEZANOST RADA