Ionic reactions of terminal alkenes with chlorine (Cl(2)), bromine (Br(2)), and iodine monochloride (ICl) are sensitive to the alkyl substituents, and the positions and number of vinyl fluorine atoms. These perturbations influence the symmetry of the halonium ion intermediates, which can be determined by the distribution of the Markovnikov to anti-Markovnikov products. A vinyl fluorine on the number-2 carbon favors an unsymmetrical intermediate with greater charge on the number-2 carbon unless the alkyl group is electron withdrawing. A vinyl fluorine on the terminal number-1 carbon favors positive charge development on that carbon unless a resonance stabilizing group is on the number-2 carbon. The symmetry of halonium ions with vinyl fluorines on both carbons-1 and -2 depends primarily on the characteristics of the alkyl substituent. Intermediates range from open-ions with the positive charge on carbon-2, to various bridged species, to open-ions on the terminal carbon.
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http://dx.doi.org/10.1021/jo030030v | DOI Listing |
Eur J Med Chem
December 2024
A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, ul. Vavilova 28, bld. 1, Moscow, 119334, Russia. Electronic address:
Thevinols and their 3-O-demethylated relatives, orvinols, are derivatives of the Diels-Alder adduct of natural alkaloid thebaine with methyl vinyl ketone. Taken together, thevinols and orvinols constitute an important family of opioid receptor (OR) ligands playing an important role in both the OR mediated antinociception and OR antagonism. Herein, we disclose for the first time the antagonist activity of the N-allyl substituted orvinol derivative fluorinated within the pharmacophore associated with C(20) and its surrounding.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
Department of Chemistry and Chemical Biology, Harvard University Cambridge, Massachusetts, 02138, United States.
Sulfenyl fluorides are organic compounds of sulfur in formal oxidation state +2 with the formula R-S-F. Although the chloride, bromide, and iodide analogues have been extensively described in the literature, arenesulfenyl fluorides remain essentially unstudied. These structures have been implicated as putative intermediates in established processes to access polyfluorinated sulfur species; however, definitive and direct evidence of their existence has not been obtained, nor has a systematic understanding of their reactivity.
View Article and Find Full Text PDFACS Org Inorg Au
December 2024
Department of Chemistry and Biomolecular Sciences and Centre for Catalysis Research and Innovation, University of Ottawa, 30 Marie Curie, Ottawa, Ontario K1N 6N5, Canada.
The integration of fluorine into medicinal compounds has become a widely used strategy to improve the biochemical and therapeutic properties of drugs. Inclusion of -CFH and -OCF fluoroalkyl groups has garnered attention due to their bioisosteric properties, enhanced lipophilicity, and potential hydrogen-bonding capability in bioactive substances. In this study, we prepared a series of stable Cu[CF(OCF)(CFH)]L complexes by insertion of commercially available perfluoro(methyl vinyl ether), CF=CF(OCF), into Cu-H bonds derived from Stryker's reagent, [CuH(PPh)], using ancillary ligands L.
View Article and Find Full Text PDFEur J Nucl Med Mol Imaging
November 2024
Department of Medical Microbiology and Infection Prevention, University of Groningen, University Medical Center Groningen, Hanzeplein 1, Groningen, 9713GZ, The Netherlands.
Introduction: Bacterial infections pose major challenges in medicine. To guide effective infection treatment, faster and more accurate diagnostic modalities are needed. Bacteria-targeted molecular imaging can meet these needs.
View Article and Find Full Text PDFACS Appl Mater Interfaces
December 2024
Department of Biomedical Engineering, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
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