The covalent linkage of phenanthrene units at 9 and 10 positions resulted in a broadening of the absorption band and a red-shift of the fluorescence band in ethanol compared with its monomer. Spatial stacking of phenanthrene units also altered the spectral shape of phosphorescence emission, and the oligomer film emitted phosphorescence at room temperature.
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J Org Chem
January 2025
Department of Chemistry, Illinois State University, Normal, Illinois 61790-4160, United States.
A series of porphyrin analogues with fused 1,10-phenanthroline units were synthesized. The proton NMR spectra for phenanthroline-fused heteroporphyrins showed significantly upfield shifted -proton resonances compared to related porphyrinoid systems and the peaks corresponding to alkyl substituents directly attached to these macrocycles were also observed further upfield. These results indicate that the presence of the phenanthroline unit leads to reduced diatropicity, but the internal NH resonance was also further upfield, a result that is inconsistent with this interpretation.
View Article and Find Full Text PDFChemistry
November 2024
Institute of Organic Chemistry of Polish Academy of Sciences, Kasprzaka 44/52, 01-224, Warsaw, Poland.
Here we present a highly versatile synthetic strategy based on twofold 6π-electrocyclization accompanied with HBr elimination as a novel approach towards centrosymmetric multi-heteroatom-doped nanographenes build around an electron-rich 1,4-dihydropyrrolo[3,2-b]pyrrole core. A straightforward synthesis from readily available substrates offers a unique possibility of fusing the 1,4-dihydropyrrolo[3,2-b]pyrrole subunit not only with carbocyclic building blocks, such as electron-deficient phenanthrenes, chrysenes, or [4]helicenes, but also with heterocyclic systems, such as benzo[b]furan and 5-thiatruxene. The clear advantage of this strategy is that there is no requirement to assemble complex scaffolds possessing bromoaryl units since bromine atom is introduced by bromination of 1,4-dihydropyrrolo[3,2-b]pyrrole core which, because of its exceptionally electron-rich character, is straightforward reaction.
View Article and Find Full Text PDFJ Colloid Interface Sci
February 2025
The Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122, China. Electronic address:
In this work, a novel bio-based polyphenol diol intermediate (VDP) was synthesized through a combination of aldimine condensation and addition reactions, utilizing vanillin, 4,4'diamino diphenylmethane (DDM), and 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide (DOPO) as reactants, then various contents of VDP was introduced covalently into the polyurethane backbone. The integration of VDP has notably improved the flame retardancy of polyurethane elastomer, the limiting oxygen index (LOI) of the elastomer was elevated from 23% to 30%, and reaches V-0 rating in the UL-94 vertical burning test. The enhancement of flame retardancy is attributed to the introduction of VDP units, which not only generate PO· and PO∙ that can capture active free radicals during combustion, but also releases non-flammable gases to improve the flame-retardant effect.
View Article and Find Full Text PDFAm J Public Health
January 2025
Patricia R. Freeman and Douglas R. Oyler are with the University of Kentucky College of Pharmacy, Department of Pharmacy Practice and Science, Lexington. Alexander Y. Walley, Trevor J. Baker, and Jeffrey H. Samet are with the Boston Medical Center, Boston, MA. T. John Winhusen is with the University of Cincinnati Department of Psychiatry and Behavioral Neuroscience, Cincinnati, OH. Emmanuel A. Oga, Christian Douglas, JaNae Holloway, Nathan A. Vandergrift, Joella W. Adams, Katherine Asman, LaShawn M. Glasgow, Charles Knott, and Gary A. Zarkin are with RTI International, Research Triangle Park, NC. Jennifer Villani and Redonna K. Chandler are with the National Institute on Drug Abuse, National Institutes of Health, Bethesda, MD. Timothy Hunt, Kitty Gelberg, James L. David, Louisa Gilbert, Dawn A. Goddard-Eckrich, and Nabila El Bassel are with the Columbia University School of Social Work, Social Intervention Group, New York, NY. Brittni Reilly is with the Massachusetts Department of Public Health, Boston. Michael S. Lyons is with Ohio State University Department of Emergency Medicine, Columbus. Candace J. Brancato is with the University of Kentucky College of Public Health, Department of Biostatistics, Lexington. Debbie M. Cheng is with the Boston University School of Public Health, Department of Biostatistics, Boston, MA. Janet E. Childerhose is and Rebecca D. Jackson was with the Ohio State University College of Medicine, Department of Internal Medicine, Columbus. Daniel J. Feaster is with the University of Miami Miller School of Medicine, Department of Public Health Sciences, Miami, FL. Hannah K. Knudsen, Michelle R. Lofwall, Katherine R. Marks, and Sharon L. Walsh are with the University of Kentucky College of Medicine, Department of Behavioral Science, Lexington. Jason T. McMullan is with the University of Cincinnati Department of Emergency Medicine, Cincinnati, OH. Carrie B. Oser is with the University of Kentucky, Department of Sociology, Lexington. Monica Roberts and Josie Watson are with the University of Kentucky Substance Use Priority Research Area, Lexington. Abigail B. Shoben is with the Ohio State University College of Public Health, Division of Biostatistics, Columbus. Michael D. Stein is with the Boston University School of Public Health, Department of Health Law, Policy, and Management, Boston, MA. Scott T. Walters is with the University of North Texas Health Science Center, School of Public Health, Fort Worth.
Addiction
January 2025
Department of Emergency Medicine, University of Ottawa, Ottawa, Canada.
Background And Aims: Buprenorphine is an evidence-based treatment for opioid use disorder, and the risk of precipitated withdrawal contributes to its underuse. The goal of this systematic review was to determine the incidence of buprenorphine-precipitated withdrawal in adults with opioid use disorder.
Methods: This systematic review was registered on PROSPERO (CRD42023437634).
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