2248-46-6Relevant academic research and scientific papers
A convenient synthetic approach to a novel class of aryldifluoromethyl pyrimidine derivatives containing strobilurin motif as insecticidal agents
Hao, Shulin,Cai, Zengfei,Zhang, Wenliang,Cao, Yangyang,Du, Xiaohua
, p. 88 - 96 (2021/10/07)
A series of aryldifluoromethyl pyrimidine compounds containing strobilurin were synthesized through bioelectronic isometric design with azoxystrobin as the lead compound and a convenient approach to aryldifluoromethylpyrimidine intermediates was developed, which features mild reaction conditions and simple operation. The title compounds and aryldifluoromethylpyrimidine intermediates were characterized by NMR and HRMS. Both 7c and 7l of the preliminary screening tests showed 100% inhibition against Mythimna separata at 100 mg/L. At 20 mg/L, the lethal rate of 7l against Mythimna separata can be up to 80%.
Silver-catalyzed decarboxylative radical allylation of α,α-difluoroarylacetic acids for the construction of CF2-allyl bonds
Wang, Pingyang,Du, Pengcheng,Sun, Qianqian,Zhang, Jianhua,Deng, Hongmei,Jiang, Haizhen
supporting information, p. 2023 - 2029 (2021/03/16)
An efficient silver-catalyzed method of decarboxylative radical allylation of α,α-difluoroarylacetic acids to build CF2-allyl bonds has been developed. Using allylsulfone as an allyl donor, α,α-difluorine substituted arylacetic acids bearing various functional groups are successfully allylated to access a series of 3-(α,α-difluorobenzyl)-1-propylene compounds in moderate to excellent yields in aqueous CH3CN solution under the mild conditions. Experimental studies disclosed that the α-fluorine substitution of arylacetic acid has a great influence on free radical activity and reactivity.
Direct Approach to 3-Fluoroindoles and 3,3-Difluoroindolines from 2,2-Difluoro-2-phenylethan-1-amines via C-H/N-H Coupling
Zhang, Lanfei,Zhang, Xiaofei,Cui, Yongmei,Yang, Chunhao
supporting information, p. 3815 - 3826 (2021/06/28)
Herein, a direct method for the synthesis of 3-fluoroindoles and 3,3-difluoroindolines from easily accessible 2,2-difluoro-2-phenyl ethan-1-amines is presented. This protocol was performed by Pd-catalyzed direct C-H/N-H coupling and employed picolinamide as a directing group. By controlling the temperature for this transformation, various 3,3-difluoroindolines and 3-fluoroindoles could be isolated with moderate to good yields.
Generation of Axially Chiral Fluoroallenes through a Copper-Catalyzed Enantioselective β-Fluoride Elimination
Liu, Peng,Mai, Binh Khanh,Nafie, Jordan,O'Connor, Thomas J.,Toste, F. Dean
supporting information, p. 13759 - 13768 (2021/09/07)
Herein we report the copper-catalyzed silylation of propargylic difluorides to generate axially chiral, tetrasubstituted monofluoroallenes in both good yields (27 examples >80%) and enantioselectivities (82-98% ee). Compared to previously reported synthetic routes to axially chiral allenes (ACAs) from prochiral substrates, a mechanistically distinct reaction has been developed: the enantiodiscrimination between enantiotopic fluorides to set an axial stereocenter. DFT calculations and vibrational circular dichroism (VCD) suggest that β-fluoride elimination from an alkenyl copper intermediate likely proceeds through a syn-β-fluoride elimination pathway rather than an anti-elimination pathway. The effects of the C1-symmetric Josiphos-derived ligand on reactivity and enantioselectivity were investigated. Not only does this report showcase that alkenyl copper species (like their alkyl counterparts) can undergo β-fluoride elimination, but this elimination can be achieved in an enantioselective fashion.
PROCESSES FOR FLUORINATION
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Paragraph 0179; 0184; 0231, (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.
Synthetic method of aromatic ring group or aromatic heterocyclic tetrazole
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Paragraph 0036-0042; 0050, (2020/12/30)
The synthetic method comprises the following steps: (1) reacting 1.0 eq of ArI or HArI with 1.2 eq of ethyl 2, 2-difluoroacetate in the presence of DMSO as a solvent and 4.0 eq of Cu under the protection of nitrogen at 30 DEG C and 50 DEG C, and purifying to obtain a first intermediate compound; (2) dissolving 1.0 eq of the first intermediate compound in a mixed solvent of THF and water, adding 2.0 eq of LiOH, reacting at room temperature for 2 hours, spin-drying the solvent, adding HCl until the pH value is equal to 3, and filtering to obtain a second intermediate compound; and (3) reacting 1.0 eq of the second intermediate compound with 2.0 eq of diphenyl azide phosphate in the presence of 2.5 eq of triethylamine by taking tert-butyl alcohol as a solvent to generate aromatic ring group or aromatic heterocyclic tetrazole. The invention provides a novel synthetic method of aromatic ring group or aromatic heterocyclic tetrazole, wherein a target compound can be more conveniently obtained, and reagents participating in the reaction are low in toxicity, mild in reaction condition, simple and safe in aftertreatment, good in product quality and suitable for large-scale production.
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.
Room Temperature Deoxyfluorination of Benzaldehydes and α-Ketoesters with Sulfuryl Fluoride and Tetramethylammonium Fluoride
Melvin, Patrick R.,Ferguson, Devin M.,Schimler, Sydonie D.,Bland, Douglas C.,Sanford, Melanie S.
supporting information, p. 1350 - 1353 (2019/03/08)
A method for the room temperature deoxyfluorination of benzaldehydes and α-ketoesters using sulfuryl fluoride and Me4NF is described. A large scope of aryl and heteroaryl substrates is demonstrated, and this method compares favorably to other common deoxyfluorination methods for many substrates.
Lewis acid-mediated defluorinative [3+2] cycloaddition/aromatization cascade of 2,2-difluoroethanol systems with nitriles
Hsieh, Min-Tsang,Lee, Kuo-Hsiung,Kuo, Sheng-Chu,Lin, Hui-Chang
supporting information, p. 1605 - 1610 (2018/03/05)
The properties of C?F bonds, including high thermal and chemical stability, make derivatization of organic fluorine-containing compounds by the activation of the C?F bond and subsequent functionalization quite challenging. We herein report a Lewis acid-mediated defluorinative cycloaddition/aromatization cascade of 2,2-difluoroethanols with nitriles as a novel synthetic method for the preparation of 2,4,5-trisubstituted oxazoles. This reaction, which involves cleavage of two C?F bonds and the consecutive formation of C?O and C?N bonds in a one-pot fashion, features a broad substrate scope and moderate to high reaction yields. Mechanistic studies revealed that the reaction is initiated by the Lewis acid-mediated ring closure of the 2,2-difluoroethanol to produce the fluoroepoxide intermediate. (Figure presented.).
Synthesis, Characterization, and Reactivity of Palladium Fluoroenolate Complexes
Arlow, Sophie I.,Hartwig, John F.
supporting information, p. 16088 - 16091 (2017/11/22)
Cross-coupling reactions of aryl groups with α-fluoro carbonyl compounds catalyzed by palladium complexes have been reported, but palladium fluoroenolate intermediates relevant to such reactions have not been isolated or even detected previously. We report the synthesis, structural characterization, and reactivity of a series of C-bound arylpalladium fluoroenolate complexes ligated by monophosphines and bisphosphines. DPPF-ligated arylpalladium fluoroenolate complexes (DPPF = 1,1-bis(diphenylphosphino)-ferrocene) derived from a monofluoroester, a difluoroester, difluoroamides, and difluoroacetonitrile underwent reductive elimination in high yields. Reductive elimination was faster from complexes containing less electron-withdrawing fluoroenolate groups and longer Pd-C(enolate) bonds than from complexes containing more electron-withdrawing fluoroenolate groups and shorter Pd-C(enolate) bonds. The rates of reductive elimination from these C-bound fluoroenolate complexes were significantly faster than those of the analogous trifluoromethyl complexes.
