352-12-5Relevant academic research and scientific papers
PROCESSES FOR FLUORINATION
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Paragraph 0179; 0184; 0214-0215; 0218, (2021/04/10)
The present technology relates to fluorination reactions. Specifically, processes useful for making the fungicide compound, DFT are disclosed. More broadly, also disclosed herein are processes useful for deoxyfluorination at the α-aromatic position of a given compound.
PROCESSES FOR FLUORINATION
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Paragraph 0188, (2020/03/05)
The present technology relates to fluorination reactions. Specifically, processes useful for making the fungicide compound, DFT are disclosed. More broadly, also disclosed herein are processes useful for deoxyfluorination at the α-aromatic position of a given compound.
Thiourea-Catalyzed C?F Bond Activation: Amination of Benzylic Fluorides
Houle, Camille,Savoie, Paul R.,Davies, Clotilde,Jardel, Damien,Champagne, Pier Alexandre,Bibal, Brigitte,Paquin, Jean-Fran?ois
supporting information, p. 10620 - 10625 (2020/07/24)
We describe the first thiourea-catalyzed C?F bond activation. The use of a thiourea catalyst and Ti(OiPr)4 as a fluoride scavenger allows the amination of benzylic fluorides to proceed in moderate to excellent yields. Preliminary results with S- and O-based nucleophiles are also presented. DFT calculations reveal the importance of hydrogen bonds between the catalyst and the fluorine atom of the substrate to lower the activation energy during the transition state.
Cobalt-Catalyzed Asymmetric Cross-Coupling Reaction of Fluorinated Secondary Benzyl Bromides with Lithium Aryl Boronates/ZnBr2
Huang, Weichen,Shen, Qilong,Wan, Xiaolong
supporting information, p. 4327 - 4332 (2020/06/27)
A cobalt-catalyzed asymmetric cross-coupling of α-bromo-α-fluorotoluene derivatives with a variety of aryl zincates derived from lithium aryl n-butyl pinacol boronates and ZnBr2 under mild reaction conditions was described. In addition to mild reaction conditions, another advantage includes the compatibility of various common functional groups such as fluoride, chloride, bromide, cyano, or ester groups. Furthermore, this protocol was successfully applied to the enantioselective synthesis of three fluorinated derivatives of biologically active compounds or drug molecules.
Expanding the repertoire of cyclopropenium ion phase transfer catalysis: Benzylic fluorination
Dempsey, Katie,Mir, Roya,Smajlagic, Ivor,Dudding, Travis
, p. 3507 - 3511 (2018/05/25)
The application of cyclopropenium ion as a phase transfer catalyst for benzylic fluorination in high yields is reported. Integral to the mechanisms of these fluorination reactions was the role of in situ derived cyclopropenium fluoride complexes, the existence of which was supported by 1H, 19F NMR and UV–Vis spectroscopy. Density functional theory calculations were applied to gain insight into the mechanism of these reactions.
Friedel-crafts reaction of benzyl fluorides: Selective activation of C-f bonds as enabled by hydrogen bonding
Champagne, Pier Alexandre,Benhassine, Yasmine,Desroches, Justine,Paquin, Jean-Franois
supporting information, p. 13835 - 13839 (2015/02/05)
A Friedel-Crafts benzylation of arenes with benzyl fluorides has been developed. The reaction produces 1,1-diaryl alkanes in good yield under mild conditions without the need for a transition metal or a strong Lewis acid. A mechanism involving activation of the C-F bond through hydrogen bonding is proposed. This mode of activation enables the selective reaction of benzylic C-F bonds in the presence of other benzylic leaving groups.
Electrochemical fluorination using halogen mediators in ionic liquid hydrogen fluoride salt
Takahashi, Kohta,Inagi, Shinsuke,Fuchigami, Toshio
, p. G3046-G3052 (2013/07/05)
In order to utilize ammomium halides (Et4NX, X=Cl, Br, I) as halogenmediator for electrocatalytic fluorination, cyclic voltammetry measurements of the halides were investigated. The catalytic current of the halides in the presence of a dithioacatal compound was observed and the macro-scale electrolysis of dithioacetals using the halogen mediator was also carried out in ionic liquid hydrogen fluoride (HF) salt to give the corresponding fluorinated products in excellent yields. The recycle use of the halogen mediator in the electrochemical fluorination was successfully demonstrated. More inexpensive halides such as potassium bromide and potassium iodide could be soluble in HF salt and worked well as halogen mediator for the electrocatalytic fluorination.
An easy access to fluoroalkanes by deoxygenative hydrofluorination of carbonyl compounds via their tosylhydrazones
Yadav, Arvind K.,Srivastava, Vishnu P.,Yadav, Lal Dhar S.
supporting information, p. 2154 - 2156 (2013/03/14)
An efficient and operationally simple synthesis of fluoroalkanes by deoxygenative hydrofluorination of carbonyl compounds via their tosylhydrazone surrogates is reported. The reaction can be carried out in a one-pot procedure directly from carbonyl compounds.
Palladium-catalyzed substitution and cross-coupling of benzylic fluorides
Blessley, George,Holden, Patrick,Walker, Matthew,Brown, John M.,Gouverneur, Veronique
supporting information; experimental part, p. 2754 - 2757 (2012/07/16)
Benzylic fluorides are suitable substrates for Pd(0)-catalyzed Tsuji-Trost substitution using carbon, nitrogen, oxygen, and sulfur nucleophiles and for cross-coupling with phenylboronic acid. For the bifunctional substrate 4-chlorobenzyl fluoride, fine-tuning of the reaction conditions allows for the regioselective displacement of either the chlorine or fluorine substituent. The leaving group ability of fluoride vs other groups displaced in substitution is CF3CO2 ≈ p-NO2C6H 4CO2 ≈ OCO2CH3 > F > CH3CO2, a ranking similar to allylic fluorides under Pd catalysis.
Recyclable polymer-supported iodobenzene-mediated electrocatalytic fluorination in ionic liquid
Sawamura, Takahiro,Kuribayashi, Shunsuke,Inagi, Shinsuke,Fuchigami, Toshio
experimental part, p. 2757 - 2760 (2010/12/25)
The electrochemical fluorination of organosulfur compounds in triethylamine/hydrofluoric acid (Et3N-5HF) with polystyrene-supported iodobenzene (PSIB) and tetraethylammonium chloride (Et4NCl) was performed successfully in an undivided cell under constant current conditions to afford the corresponding fluorinated compounds in moderate to good yields. Recycle use of the PSIB could be achieved due to its easy separation. Notably, the mediatory activity of the iodobenzene derivative was not appreciably changed even after 10 recycle uses.
