Artykuły IChO PAN
https://depot.ceon.pl/handle/123456789/20789
2024-03-29T08:14:14ZSinglet Fission in a New Series of Systematically Designed Through-space Coupled Tetracene Oligomers
https://depot.ceon.pl/handle/123456789/24062
Singlet Fission in a New Series of Systematically Designed Through-space Coupled Tetracene Oligomers
Majdecki, Maciej; Hsu, Chao-Hsien; Wang, Chih-Hsing; Shi, Emily Hsue-Chi; Zakrocka, Magdalena; Wei, Yu-Chen; Chen, Bo-Han; Lu, Chih-Hsuan; Yang, Shang-Da; Chou, Pi-Tai; Gaweł, Przemysław
Singlet fission (SF) holds great promise for current photovoltaic technologies, where tetracenes, with their relatively high triplet energies, play a major role for application in silicon-based solar cells. However, the SF efficiencies in tetracene dimers are low due to the unfavorable energetics of their singlet and triplet energy levels. In the solid state, tetracene exhibits high yields of triplet formation through SF, raising great interest about the underlying mechanisms. To address this discrepancy, we designed and prepared a novel molecular system based on a hexaphenylbenzene core decorated with 2 to 6 tetracene chromophores. The spatial arrangement of tetracene units, induced by steric hindrance in the central part, dictates through-space coupling, making it a relevant model for solid-state chromophore organization. We then revealed a remarkable increase in SF quantum yield with the number of tetracenes, reaching quantitative (196 %) triplet pair formation in hexamer. We observed a short-lived correlated triplet pair and limited magnetic effects, indicating ineffective triplet dissociation in these through-space coupled systems. These findings emphasize the crucial role of the number of chromophores involved and the interchromophore arrangement for the SF efficiency. The insights gained from this study will aid designing more efficient and technology-compatible SF systems for applications in photovoltaics.
2024-01-01T00:00:00ZComputational synthesis design for controlled degradation and revalorization
https://depot.ceon.pl/handle/123456789/23996
Computational synthesis design for controlled degradation and revalorization
Żądło-Dobrowolska, Anna; Molga, Karol; Kolodiazhna, Olga O.; Szymkuć, Sara; Moskal, Martyna; Grzybowski, Bartosz A.
Degradation of larger and undesired/harmful molecules into smaller and, ideally, value-added products is one of the important facets of circular chemistry. This task may be cumbersome to chemists who are accustomed to plan syntheses using bond-forming rather than bond-breaking methodologies. This work describes a forward-synthesis algorithm that can guide such degradation-oriented analyses. This algorithm uses a broad knowledge-base of degradative and related reactions and applies them to arbitrary small-molecule feeds to generate large synthetic networks within which it then traces degradative pathways that are chemically sound and lead to value-added products. Predictions of the algorithm are validated by proof-of-concept experiments entailing degradation and revalorization of two biomass feeds, D-glucose and quinine.
2024-01-01T00:00:00ZVitamin B12: An efficient cobalt catalyst for sustainable generation of radical species
https://depot.ceon.pl/handle/123456789/23975
Vitamin B12: An efficient cobalt catalyst for sustainable generation of radical species
Giedyk, Maciej; Gryko, Dorota
Vitamins are organic molecules that are essential for the proper functioning of mammalian cells. Among them, there is only one organometallic molecule: vitamin B12, a natural cobalt complex that is involved in DNA synthesis and regulation, the functioning of the nervous system, the formation of red blood cells, etc. Being a co-factor for enzymes dependent on adenosylcobalamin and methylcobalamin, vitamin B12 plays a crucial role in isomerization, methyl transfer, and dehalogenation reactions. Its activity, however,
is not limited to the reactions taking place under physiological settings. It has been widely explored as a preferable catalyst for sustainable organic synthesis, and an abundance of B12-catalyzed strategies has already been developed. In this perspective, we highlight the underlying principles and catalytic propensity of vitamin B12 in the generation of C-centered radicals from various precursors and their use in the synthesis of important molecular scaffolds. We also discuss challenges for future discoveries.
2022-01-01T00:00:00ZThe Study on Timolol and Its Potential Phototoxicity Using Chemical, In Silico and In Vitro Methods
https://depot.ceon.pl/handle/123456789/23889
The Study on Timolol and Its Potential Phototoxicity Using Chemical, In Silico and In Vitro Methods
Lejwoda, Karolina; Gumieniczek, Anna; Filip, Agata; Naumczuk, Beata
Amidži´c Klari´c, Daniela; Mornar, Ana
Timolol (TIM) is a non-selective ß-adrenergic receptor antagonist used orally for the treatment of hypertension and heart attacks, and topically for treating glaucoma; lately, it has also been used in some specific dermatological problems. In the present study, its photodegradation and potential risk of phototoxicity were examined using chemical, in silico and in vitro methods. The UV/VIS irradiated solutions of TIM at pH 1–13 were subjected to LC-UV and UPLC-HRMS/MS
analyses showing pseudo first-order kinetics of degradation and several degradation products. The structures of these photodegradants were elucidated by fragmentation path analysis based on high
resolution (HR) fragmentation mass spectra, and then used for toxicity evaluation using OSIRIS Property Explorer and Toxtree. Potential risk of phototoxicity was also studied using chemical tests for detecting ROS under UV/VIS irradiation and in vitro tests on BALB/c 3T3 mouse fibroblasts (MTT, NRU and Live/Dead tests). TIM was shown to be potentially phototoxic because of its UV/VIS absorptive properties and generation ROS during irradiation. As was observed in the MTT and NRU tests, the co-treatment of fibroblasts with TIM and UV/VIS light inhibited cell viability, especially when concentrations of the drug were higher than 50 μg/mL.
2024-01-01T00:00:00Z