Aryl ketones are often used as photosensitizers and photoinitiators. Free radical intermediates have been suggested, but not confirmed, to be generated after photoirradiation. Here we found, unexpectedly, that a persistent radical was produced from di-2-pyridyl ketone after UV irradiation, which was detected by the direct ESR method. Interestingly, the persistent radical was very sensitive to oxygen and the pH of the reaction medium. A similar persistent radical was also observed from phenyl-2-pyridyl ketone, but not from 3-benzoylpyridine, 4-benzoylpyridine, and benzophenone, suggesting that the presence of a carbonyl group connected to the -position of the pyridine ring is critical for such radical production. By complementary applications of ESR, HPLC, and ESI-Q-TOF-MS, the possible chemical structures of the persistent radical and final product were identified, and the possible underlying reaction mechanism was proposed. This represents the first report on UV-induced persistent radical generation from 2-pyridyl ketones, which should be of great significance for future studies.
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http://dx.doi.org/10.1021/acs.jpclett.4c02657 | DOI Listing |
J Environ Manage
January 2025
Department of Sanitary Engineering, Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Narutowicza 11/12 Str., 80-233, Gdansk, Poland; School of Civil, Environmental, and Architectural Engineering, College of Engineering, Korea University, 145 Anam-ro, Seongbuk-gu, Seoul, 02841, Republic of Korea. Electronic address:
Advanced Oxidation Processes (AOPs) have proven to be an effective solution for chemical wastewater treatment, particularly for degradation of organic pollutants, especially dyes. Ozonation is recognized as one of the most prevalent AOPs. Nevertheless, some cases show a lowered efficiency of O utilization which is attributed to its inadequate distribution in the treated water causing low residence time, low mass transfer coefficient as well as shorter half-life.
View Article and Find Full Text PDFNat Commun
January 2025
Charles D. Davidson School of Chemical Engineering, Purdue University, West Lafayette, IN, USA.
Spin currents have long been suggested as a potential solution to addressing circuit miniaturization challenges in the semiconductor industry. While many semiconducting materials have been extensively explored for spintronic applications, issues regarding device performance, materials stability, and efficient spin current generation at room temperature persist. Nonconjugated paramagnetic radical polymers offer a unique solution to these challenges.
View Article and Find Full Text PDFEnviron Sci Technol
January 2025
Key Laboratory of Jiangxi Province for Persistent Pollutants Prevention Control and Resource Reuse, Nanchang Hangkong University, Nanchang 330063, China.
The traditional treatment of toxic and refractory copper(II)-ethylenediaminetetraacetic acid chelate (Cu(II)-EDTA) in electroless effluents often generates hazardous waste and secondary nitrogen-containing pollutants without maximizing the resource recovery. This study demonstrates a facile strategy to simultaneously recover Cu and EDTA ligands from Cu(II)-EDTA electroless effluent with commercially available metallic Cu and formaldehyde. In this strategy, metallic Cu is used to activate formaldehyde, a prevalent yet often overlooked cocontaminant in Cu(II)-EDTA effluents, to produce highly reductive hydrogen radical (H), which in situ decomplex Cu(II)-EDTA, reduces the central Cu(II) into metallic Cu, and release EDTA ligand.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, and MoE Frontiers Science Center for Precision Oncology, University of Macau, Taipa, Macau SAR 999078, China.
Despite the development of various controlled release systems for antitumor therapies, off-target side effects remain a persistent challenge. In situ therapeutic synthesis from biocompatible substances offers a safer and more precise alternative. This study presents a hypoxia-initiated supramolecular free radical system capable of inducing intracellular polymerization, thereby disrupting the cytoskeleton and organelles within 4T1 cells.
View Article and Find Full Text PDFEnviron Sci Process Impacts
January 2025
Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education), School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
Environmentally persistent free radicals (EPFRs) have been widely detected in polycyclic aromatic hydrocarbon (PAH)-contaminated soils, but the activation of persulfate by inherent EPFRs in PAH-contaminated soil for the transformation of PAHs remains unclear. In the present study, benzo[]pyrene (B[]P) was selected as a representative PAH and its transformation in a persulfate/B[]P-contaminated soil system was studied without the addition of any other activator. Results indicated that EPFRs in the soil activated persulfate to produce reactive oxygen species (ROS) and degraded B[]P.
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