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Search for "fluorine" in Full Text gives 438 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Helicene synthesis by Brønsted acid-catalyzed cycloaromatization in HFIP [(CF3)2CHOH]

  • Takeshi Fujita,
  • Noriaki Shoji,
  • Nao Yoshikawa and
  • Junji Ichikawa

Beilstein J. Org. Chem. 2021, 17, 396–403, doi:10.3762/bjoc.17.35

Graphical Abstract
  • fluorine, which helps to generate cations but does not affect cationic reactions [23][24][25][26][27]. Thus, HFIP greatly facilitates reactions via cationic intermediates [28]. In the presence of a catalytic amount of trifluoromethanesulfonic acid in HFIP, (biaryl-2-yl)acetoaldehydes or their acetal
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Published 09 Feb 2021

CF3-substituted carbocations: underexploited intermediates with great potential in modern synthetic chemistry

  • Anthony J. Fernandes,
  • Armen Panossian,
  • Bastien Michelet,
  • Agnès Martin-Mingot,
  • Frédéric R. Leroux and
  • Sébastien Thibaudeau

Beilstein J. Org. Chem. 2021, 17, 343–378, doi:10.3762/bjoc.17.32

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  • cations is probably the α-(trifluoromethyl) carbocation. Many efforts are currently devoted to develop methods allowing the efficient insertion of fluorine atoms or fluorinated groups into organic molecules [7][8][9][10][11][12]. The increasing demand for fluorinated scaffolds, due to the striking
  • beneficial effects generally resulting from the introduction of these fluorinated motifs [13], also participated in this development. These fluorine effects are nowadays remarkably established in many domains, including medicinal, organic, and organometallic chemistry, catalysis, chemical biology, and
  • optimization of the geometry for CF3CH2+ at the STO-3G level led to an energy minimum, in which one of the fluorine atoms is significantly closer to the positive carbon center (Figure 1, top, θ = 101°) [24]. However, exactly the same structural distortion was calculated for the ethyl cation. Furthermore, the
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Published 03 Feb 2021

19F NMR as a tool in chemical biology

  • Diana Gimenez,
  • Aoife Phelan,
  • Cormac D. Murphy and
  • Steven L. Cobb

Beilstein J. Org. Chem. 2021, 17, 293–318, doi:10.3762/bjoc.17.28

Graphical Abstract
  • use of 19F NMR in the broad field of chemical biology [Cobb, S. L.; Murphy, C. D. J. Fluorine Chem. 2009, 130, 132–140] and present here a summary of the literature from the last decade that has the technique as the central method of analysis. The topics covered include the synthesis of new
  • biosynthesis and biodegradation of fluorinated organic compounds is also described. Keywords: biotransformation; chemical biology; fluorine; 19F NMR; probes; protein structure; Introduction Although fluorine is abundant in the environment, it is not a nutrient nor is it a feature of biochemistry for most
  • ]. Furthermore, owing to the lack of naturally-occurring fluorinated compounds, fluorine is a useful probe to investigate structure and mechanism of biological molecules. Central to these studies is fluorine-19 nuclear magnetic resonance spectroscopy (19F NMR), which allows the user to readily visualize changes
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Published 28 Jan 2021

Diels–Alder reaction of β-fluoro-β-nitrostyrenes with cyclic dienes

  • Savva A. Ponomarev,
  • Roman V. Larkovich,
  • Alexander S. Aldoshin,
  • Andrey A. Tabolin,
  • Sema L. Ioffe,
  • Jonathan Groß,
  • Till Opatz and
  • Valentine G. Nenajdenko

Beilstein J. Org. Chem. 2021, 17, 283–292, doi:10.3762/bjoc.17.27

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  • activation parameters. Furthermore, the synthetic utility of the cycloadducts obtained was demonstrated. Keywords: Diels–Alder reaction; fluorine; nitrostyrene; norbornene; stereochemistry; Introduction Organofluorine compounds play an exceptionally important role in various fields of science and
  • technology. The incorporation of fluorine into molecules can significantly influence their pharmacokinetic and physicochemical properties and enhance their metabolic and chemical stability [1][2][3][4][5]. For instance, nearly a quarter of the currently manufactured agrochemical and pharmaceutical products
  • contains at least one fluorine atom [6][7][8]. Fluorinated functional materials have also found wide application as durable ion exchange membranes, e.g., in fuel cells [9][10][11], as thermoplastic polymers [12][13][14], in electronic and optoelectronic technologies [15], and in liquid crystal display
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Published 27 Jan 2021

The preparation and properties of 1,1-difluorocyclopropane derivatives

  • Kymbat S. Adekenova,
  • Peter B. Wyatt and
  • Sergazy M. Adekenov

Beilstein J. Org. Chem. 2021, 17, 245–272, doi:10.3762/bjoc.17.25

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  • .17.25 Abstract Recently, the functionalization of organic molecules with fluorine substituents has grown rapidly due to its applications in such fields as medicine, agriculture or materials sciences. The aim of this article is to review the importance of 1,1-difluorocyclopropane derivatives in synthesis
  • . It will examine the role of the fluorine substituents in both ring-forming and ring-opening reactions, as well as methods for obtaining difluorocyclopropanes as single enantiomers. Several examples are provided to highlight the biological importance of this class of compounds. Keywords: biological
  • the gem-dihalomethylene fragment. Thus, they are of interest not only for the direct application as biologically active substances and functional materials but also as precursors to other fluorine-containing compounds [1][2]. Fluorine forms stable bonds to carbon and due to its high electronegativity
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Published 26 Jan 2021

Decarboxylative trifluoromethylthiolation of pyridylacetates

  • Ryouta Kawanishi,
  • Kosuke Nakada and
  • Kazutaka Shibatomi

Beilstein J. Org. Chem. 2021, 17, 229–233, doi:10.3762/bjoc.17.23

Graphical Abstract
  • synthesizing substituted pyridines are in high demand in pharmaceutical and agricultural chemistry [1][2]. Because of the unique features of fluorine atoms, fluorinated functional groups have also been recognized as important substructures in the design of medicinally relevant compounds [3][4][5][6
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Published 25 Jan 2021
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  • thermally activated delayed fluorescence (TADF) emitters. In the present study, we investigate computationally the potential of other fluorine-containing acceptors, trifluoromethoxy (OCF3), trifluoromethylthio (SCF3), and pentafluorosulfanyl (SF5), within two families of donor–acceptor TADF emitters. Time
  • within TADF emitter design (Figure 1) [25][26][27]. In the present study, we report on the impact of incorporating other fluorine-containing electron-withdrawing groups beyond trifluoromethyl (CF3), including trifluoromethoxy (OCF3), trifluoromethylthio (SCF3), and pentafluorosulfanyl (SF5) groups, and
  • , and 2CzBP of −1.70 eV, −1.63 eV, and −1.67 eV, respectively, are much deeper those of the fluorine-containing emitters in Figure 3, which is a reflection of the greater conjugation length present in compounds with an extended π-accepting framework. The corresponding ΔEg of 2CzBN (4.19 eV), 2CzTRZ
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Published 21 Jan 2021

A sustainable strategy for the straightforward preparation of 2H-azirines and highly functionalized NH-aziridines from vinyl azides using a single solvent flow-batch approach

  • Michael Andresini,
  • Leonardo Degannaro and
  • Renzo Luisi

Beilstein J. Org. Chem. 2021, 17, 203–209, doi:10.3762/bjoc.17.20

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  • was found to be efficient with vinyl azides carrying aryls substituted with chlorine (2b), fluorine (2c), and bromide (2e–g). In details, ortho-, meta-, and para-bromophenyl derivatives were quantitatively transformed into the corresponding 2H-azirines 2e–g without substantial differences. Similarly
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Published 20 Jan 2021

Facile preparation and conversion of 4,4,4-trifluorobut-2-yn-1-ones to aromatic and heteroaromatic compounds

  • Takashi Yamazaki,
  • Yoh Nakajima,
  • Minato Iida and
  • Tomoko Kawasaki-Takasuka

Beilstein J. Org. Chem. 2021, 17, 132–138, doi:10.3762/bjoc.17.14

Graphical Abstract
  • ; salicylate derivatives; Introduction It is well known that the incorporation of a fluorine atom or a fluorine-containing group into organic compounds sometimes affects their original biological activities [1][2][3], and thus the development of methods for the construction of such molecules with this atom or
  • group is an important task. During our research in the field of fluorine chemistry, we have previously developed methods to get convenient access to CF3-containing propargylic alcohols 1 using 2-bromo-3,3,3-trifluoropropene [4][5] as well as 1-chloro-3,3,3-trifluoropropene [6] as a substrate and to
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Published 15 Jan 2021

Tuning the solid-state emission of liquid crystalline nitro-cyanostilbene by halogen bonding

  • Subrata Nath,
  • Alexander Kappelt,
  • Matthias Spengler,
  • Bibhisan Roy,
  • Jens Voskuhl and
  • Michael Giese

Beilstein J. Org. Chem. 2021, 17, 124–131, doi:10.3762/bjoc.17.13

Graphical Abstract
  • fluorine substitution of the aromatic halogen bond donor on the liquid crystallinity and the photo-response of halogen-bonded liquid crystals [12]. However, all reported halogen-bonded liquid crystals rely on the halogen-bond-acceptor capability of pyridyl units and so far, no study on the fluorescence
  • induction of liquid crystallinity in our assemblies, we synthesised a series of azo compounds with decreasing fluorination degree at the halogen bond donating iodobenzene [12]. Reducing the number of the fluorine atoms at the halogen bond donating moiety lowers the polarisation of the iodine atom and thus
  • temperature, which indicates that the strength of the halogen bond is not the only contributor to the mesomorphic behaviour of the halogen-bonded materials. The change in the electronic anisotropy by unsymmetrical substitution with fluorine as present in F3Az will also have an impact on the dispersion
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Published 14 Jan 2021

Synthesis of aryl 2-bromo-2-chloro-1,1-difluoroethyl ethers through the base-mediated reaction between phenols and halothane

  • Yukiko Karuo,
  • Ayaka Kametani,
  • Atsushi Tarui,
  • Kazuyuki Sato,
  • Kentaro Kawai and
  • Masaaki Omote

Beilstein J. Org. Chem. 2021, 17, 89–96, doi:10.3762/bjoc.17.9

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  • utility of halothane for the synthesis of aryl gem-difluoroalkyl ethers containing the bromochloromethyl group. Keywords: aryl 1,1-difluoroethyl ether; 1,1-difluoroethene; fluorine compound; halothane; phenol; Introduction Molecules containing fluoroalkyl groups are of interest in pharmaceutical and
  • agrochemical sciences because deliberately incorporated fluorine atoms often change the chemical properties of the parent molecules by improving the absorption, resistance to metabolism, and pharmacological activities. To date, difluoromethyl or difluoromethylene compounds have been studied extensively as well
  • carbon that was explained by an orbital interaction between the n orbital (fluorine) and the π orbital [44]. A literature survey revealed that Yagupol’skii et al. have achieved the first synthesis of aryl or alkyl 2-bromo-2-chloro-1,1-difluoroethyl ethers by the reaction of alcohols with halothane as
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Published 11 Jan 2021

Benzothiazolium salts as reagents for the deoxygenative perfluoroalkylthiolation of alcohols

  • Armin Ariamajd,
  • Nils J. Gerwien,
  • Benjamin Schwabe,
  • Stefan Dix and
  • Matthew N. Hopkinson

Beilstein J. Org. Chem. 2021, 17, 83–88, doi:10.3762/bjoc.17.8

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  • directly from readily available alcohols. Keywords: alcohols; benzothiazolium salts; deoxygenative reactions; fluorine; perfluoroalkylthiolation; thioethers; Introduction The incorporation of fluorine-containing groups into organic molecules to modulate their biological or physical properties is nowadays
  • a common strategy employed in the development of pharmaceuticals [1][2][3][4], agrochemicals [5] and materials [6]. Recent years have seen a surge in interest in emerging fluorinated motifs, which can offer improved performance over single fluorine atoms or perfluoroalkyl substituents. The
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Published 08 Jan 2021

Synthesis of tetrafluorinated piperidines from nitrones via a visible-light-promoted annelation reaction

  • Vyacheslav I. Supranovich,
  • Igor A. Dmitriev and
  • Alexander D. Dilman

Beilstein J. Org. Chem. 2020, 16, 3104–3108, doi:10.3762/bjoc.16.260

Graphical Abstract
  • heterocyclic compounds play an important role in pharmaceutical industry and related areas [1][2]. Among the variety of aromatic and saturated structures, the piperidine ring has a special role, as it is the most widely occurring form of nitrogen in FDA-approved drugs [3]. The ability of fluorine atoms to
  • modify basicity, lipophilicity, as well as the hydrogen-bonding properties of amines [4][5] makes fluorinated piperidines [6][7] attractive targets in medicinal chemistry [8][9]. Previous efforts were mainly focused on the synthesis of mono- and difluorinated compounds. A single fluorine atom is
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Published 29 Dec 2020

An atom-economical addition of methyl azaarenes with aromatic aldehydes via benzylic C(sp3)–H bond functionalization under solvent- and catalyst-free conditions

  • Divya Rohini Yennamaneni,
  • Vasu Amrutham,
  • Krishna Sai Gajula,
  • Rammurthy Banothu,
  • Murali Boosa and
  • Narender Nama

Beilstein J. Org. Chem. 2020, 16, 3093–3103, doi:10.3762/bjoc.16.259

Graphical Abstract
  • ) gave the expected product 3c along with the dehydrated product 4c (Table 2, entry 3). Substrates containing a halogen, such as fluorine, chlorine, and bromine, were efficiently reacted to afford the products 3e–h in successively moderate yields (Table 2, entries 5–8). Notably, 3-fluorobenzaldehyde (2e
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Published 23 Dec 2020

Silver-catalyzed synthesis of β-fluorovinylphosphonates by phosphonofluorination of aromatic alkynes

  • Yajing Zhang,
  • Qingshan Tian,
  • Guozhu Zhang and
  • Dayong Zhang

Beilstein J. Org. Chem. 2020, 16, 3086–3092, doi:10.3762/bjoc.16.258

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  • subsequent fluorine atom transfer. Keywords: β-fluorovinylphosphonates; fluorine atom transfer; P-centered radical; silver catalysis; three-component reaction; Introduction As one of the most important topics in organic chemistry, the introduction of fluorine and phosphorus atoms into double bonds is an
  • attractive approach for the synthesis of a variety of valuable organic compounds [1][2][3][4][5][6][7]. Although progress has been achieved in the formation of C(sp2)–F bonds from various substrates [8][9][10][11][12][13], new catalytic reactions to introduce fluorine and phosphorus are seldom reported
  • is the most rapid and convenient one (Scheme 1). Although studies on alkyne difunctionalization are ongoing [23], the successful attachment of a fluorine atom to the resulting alkene through transition metal catalysis remains a challenge. In particular, the phosphonofluorination of alkynes for the
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Published 18 Dec 2020

Deoxyfluorination of acyl fluorides to trifluoromethyl compounds by FLUOLEAD®/Olah’s reagent under solvent-free conditions

  • Yumeng Liang,
  • Akihito Taya,
  • Zhengyu Zhao,
  • Norimichi Saito and
  • Norio Shibata

Beilstein J. Org. Chem. 2020, 16, 3052–3058, doi:10.3762/bjoc.16.254

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  • -5888, Japan Pharmaceutical Division, Ube Industries, Ltd., Seavans North Bldg, 1-2-1 Shibaura, Minato-ku, Tokyo 105-8449, Japan Institute of Advanced Fluorine-Containing Materials, Zhejiang Normal University, 688 Yingbin Avenue, 321004 Jinhua, China 10.3762/bjoc.16.254 Abstract A new protocol enabling
  • trifluoromethyl compounds under the same reaction conditions. A reaction mechanism is proposed. Keywords: acyl fluorides; deoxyfluorination; fluorine; solvent-free; trifluoromethyl group; Introduction Due to an impressively wide effect of fluorine on the biological activity, the insertion of fluorine atoms or
  • fluorine-containing functional groups into organic molecules has become a common strategy in pharmaceutical and agrochemical industries [1][2][3][4][5]. Among various fluorine-containing functional groups, the trifluoromethyl (CF3) group has received countless attention in the design of novel drugs [6][7
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Published 14 Dec 2020

Metal-free nucleophilic trifluoromethylselenolation via an iodide-mediated umpolung reactivity of trifluoromethylselenotoluenesulfonate

  • Kevin Grollier,
  • Alexis Taponard,
  • Arnaud De Zordo-Banliat,
  • Emmanuel Magnier and
  • Thierry Billard

Beilstein J. Org. Chem. 2020, 16, 3032–3037, doi:10.3762/bjoc.16.252

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  • . Metal-free nucleophilic trifluoromethylselenolations have been then performed with this in situ-generated anion. Perfluoroalkylselenolations have also been described. Keywords: fluorine; nucleophilic substitution; perfluoroalkylselenolation; selenium; trifluoromethylselenolation; Introduction Because
  • of the peculiar properties of the fluorine atom, fluorinated compounds gained a growing interest over the last decades and found applications in a large panel of fields from materials to life sciences [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Fluorinated motifs bring to molecules specific
  • grateful to the CNRS and the French Ministry of Research for financial support. The French Fluorine Network is also acknowledged for its support.
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Published 10 Dec 2020

Controlled decomposition of SF6 by electrochemical reduction

  • Sébastien Bouvet,
  • Bruce Pégot,
  • Stéphane Sengmany,
  • Erwan Le Gall,
  • Eric Léonel,
  • Anne-Marie Goncalves and
  • Emmanuel Magnier

Beilstein J. Org. Chem. 2020, 16, 2948–2953, doi:10.3762/bjoc.16.244

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  • hexafluoride; Introduction Sulfur hexafluoride (SF6) is a fluorinated gas firstly identified in 1900 by Henry Moissan [1]. The strategy applied at industrial level to obtain SF6 uses sulfur in the presence of molecular fluorine. Sulfur hexafluoride possesses the particularity of being an inert gas both
  • potential of −2.3 V/SRE; (left). 19F NMR expansion of the final mixture. Funding S.B. thanks the French Ministry of Research for a Ph.D. grant. The Rhodia-Solvay company is gratefully acknowledged for the gift of sulfur hexafluoride. The French Fluorine Network (GIS Fluor) is acknowledged for financial
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Published 01 Dec 2020

Fluorine effect in nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-β-D-hexopyranose

  • Danny Lainé,
  • Vincent Denavit,
  • Olivier Lessard,
  • Laurie Carrier,
  • Charles-Émile Fecteau,
  • Paul A. Johnson and
  • Denis Giguère

Beilstein J. Org. Chem. 2020, 16, 2880–2887, doi:10.3762/bjoc.16.237

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  • approach using Et3N·3HF as an alternative to the DAST reagent. We controlled the stereochemistry of the nucleophilic fluorination at C4 of 1,6-anhydro-2,3-dideoxy-2,3-difluoro-4-O-triflate-β-ᴅ-talopyranose using Et3N·3HF or in situ generated Et3N·1HF. The influence of the fluorine atom at C2 on reactivity
  • at C4 could contribute to a new fluorine effect in nucleophilic substitution. Finally, with the continuous objective of synthesizing novel multi-vicinal fluorosugars, we prepared one difluorinated and one trifluorinated alditol analogue. Keywords: deoxyfluorination; Et3N·3HF; fluorine effect
  • groups by fluorine atoms arise from their similarities in term of polarity and isosteric relationship [3][8]. For a long time, fluorinated carbohydrates have been used as a method to stabilize glycosidic bonds [9][10][11] or for epitope mapping [12][13]. More recently, heavily fluorinated carbohydrates
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Published 25 Nov 2020

Synthesis of purines and adenines containing the hexafluoroisopropyl group

  • Viacheslav Petrov,
  • Rebecca J. Dooley,
  • Alexander A. Marchione,
  • Elizabeth L. Diaz,
  • Brittany S. Clem and
  • William Marshall

Beilstein J. Org. Chem. 2020, 16, 2739–2748, doi:10.3762/bjoc.16.224

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  • fluorine and polyfluoroalkyl substituents into organic molecules remains a challenging problem in the synthesis of fluorinated biologically active compounds, especially larger moieties, such as C2F5, CF(CF3)2, and CH(CF3)2. With respect to the hexafluoroisopropyl group, the methods are limited to a
  • investigational therapeutic agents, including antitumorals and antivirals […]” [8]. Interestingly, most fluorine-containing benzimidazoles contain the fluorinated substituent either on the aromatic ring or on a side chain connected to the aromatic ring; examples of benzimidazoles containing a fluoroalkyl group
  • mentioned above, the broadening of the resonances corresponding to the CF3 group as observed in the 19F NMR spectra of derivatives 3a, 4a, and 4b at ambient temperature is likely to be related to a restricted rotation around the C–N bond as a result of the steric interaction between the fluorine atoms of
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Published 11 Nov 2020

Asymmetric Mannich reactions of (S)-N-tert-butylsulfinyl-3,3,3-trifluoroacetaldimines with yne nucleophiles

  • Ziyi Li,
  • Li Wang,
  • Yunqi Huang,
  • Haibo Mei,
  • Hiroyuki Konno,
  • Hiroki Moriwaki,
  • Vadim A. Soloshonok and
  • Jianlin Han

Beilstein J. Org. Chem. 2020, 16, 2671–2678, doi:10.3762/bjoc.16.217

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  • -nucleophile; CF3-aldimine; fluorinated propargylamine; Introduction In recent years, substitution of hydrogen by fluorine atoms or fluorine-containing groups usually provides unexpected biological and physicochemical properties, which thus has become an established approach for the development of
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Published 29 Oct 2020

Vicinal difluorination as a C=C surrogate: an analog of piperine with enhanced solubility, photostability, and acetylcholinesterase inhibitory activity

  • Yuvixza Lizarme-Salas,
  • Alexandra Daryl Ariawan,
  • Ranjala Ratnayake,
  • Hendrik Luesch,
  • Angela Finch and
  • Luke Hunter

Beilstein J. Org. Chem. 2020, 16, 2663–2670, doi:10.3762/bjoc.16.216

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  • which the C–F bonds align gauche (I and II, Figure 1) [22]. Separately, the presence of fluorine on the α-carbon of a tertiary amide is known to restrict the Cα–C(O) bond to a small set of low-energy rotamers (III–V, Figure 1) [23]. Intriguingly, studies of simple molecules containing either F–C–C–F or
  • feature of structures 2a,b (Figure 2) is that both, the α-fluorine and the β-fluorine atoms of each structure make close contacts with the hydrogen atoms on the piperidine ring (2.08–2.34 Å). This manifests in the observation of a through-space coupling (J = 1.9 Hz) between the α-fluorine and a piperidine
  • hydrogen in the experimental NMR spectrum of 2 (i.e., spins 6/7, Figure 2). The attractive F···H interactions might explain why the amide bond is twisted by 11–20° from planarity in 2a,b. In structure 2c, only the α-fluorine makes close contacts with hydrogens on the piperidine ring, and the amide is
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Published 28 Oct 2020

Activation of pentafluoropropane isomers at a nanoscopic aluminum chlorofluoride: hydrodefluorination versus dehydrofluorination

  • Maëva-Charlotte Kervarec,
  • Thomas Braun,
  • Mike Ahrens and
  • Erhard Kemnitz

Beilstein J. Org. Chem. 2020, 16, 2623–2635, doi:10.3762/bjoc.16.213

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  • reaction mixture [33]. It was demonstrated that starting from 2-chloro-3,3,3-trifluoropropene (HFO-1233xf) in the presence of fluorinated Cr2O3 as a catalyst and HF, 2,3,3,3-tetrafluoropropene (HFO-1234yf, 1) is generated by the replacement of the chlorine substituent with a fluorine atom, and is further
  • has been added for the activation of C–F bonds at ACF [16][39][47]. Several patents cover the transformation of 10a by dehydrofluorination at chromia-based catalysts, but the reaction temperatures were above 200 °C [17][51][52]. Mechanistically, an abstraction of a fluorine from the CH2F group by the
  • bond activation at the primary carbon–fluorine bond in 10a, generating FSiEt3, the corresponding carbenium-like species, and a surface-bound hydride. At this stage, either the hydrodefluorination product 13 can be generated, or dehydrofluorination occurs to furnish the olefin 1 and H2, both in the
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Published 23 Oct 2020

Synthesis of novel fluorinated building blocks via halofluorination and related reactions

  • Attila Márió Remete,
  • Tamás T. Novák,
  • Melinda Nonn,
  • Matti Haukka,
  • Ferenc Fülöp and
  • Loránd Kiss

Beilstein J. Org. Chem. 2020, 16, 2562–2575, doi:10.3762/bjoc.16.208

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  • Deoxo-Fluor®. The fluorine-containing products thus obtained were subjected to elimination reactions, yielding various fluorine-containing small-molecular entities. Keywords: fluorine; fluoroselenation; functionalization; halofluorination; stereocontrol; Introduction The effects of fluorine on
  • discovering new reagents and conditions for the introduction of fluorine and fluorine-containing groups into a certain organic molecule [11][12][13][14][15][16][17][18], several known methods have been studied and improved over the past decade. One such long-known method is halofluorination. During this
  • process, an alkene reacts with a halogen cation to form a halonium ion, which immediately undergoes ring opening by fluoride to form a vicinal halofluoride (see Scheme 1). The overall result is an anti-addition of the XF moiety (X = Cl, Br, I) across the double bond. Since many nucleophilic fluorine
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Published 16 Oct 2020

Conformational preferences of fluorine-containing agrochemicals and their implications for lipophilicity prediction

  • Daniela Rodrigues Silva,
  • Joyce K. Daré and
  • Matheus P. Freitas

Beilstein J. Org. Chem. 2020, 16, 2469–2476, doi:10.3762/bjoc.16.200

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  • soil sorption and bioconcentration of organic compounds. Since the C–F bond is the most polar in organic chemistry, the orientation of fluorine substituents originating from the rotation around C–C(F) bonds should affect the polarity and, consequently, the physicochemical and biological properties of
  • fluorine-containing agrochemicals. Accordingly, this study aims to determine the most likely conformers of some fluorine-containing agrochemicals and to correlate their molecular dipole moments with the respective n-octanol/water partition coefficients (log P), in order to investigate the dependence of the
  • helps in explaining the expressive amount of fluorine-containing agrochemical candidates (around 30%) as well as pharmaceuticals (around 20%) [5][6]. In this sense, the chemistry of fluorine-containing compounds has been extensively investigated in order to better understand the effects of fluorination
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Published 05 Oct 2020
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