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91.
Liubov I. Panferova Grigory N. Chernov Vitalij V. Levin Vladimir A. Kokorekin Alexander D. Dilman 《Tetrahedron》2018,74(50):7136-7142
A method for the synthesis of 3,3-difluorotetrahydrofurans from iododifluoromethylated alcohols and 1,1-diarylethylenes is described. The reaction is performed under irradiation with 400?nm light emitting diodes in the presence of a cationic iridium(III) photocatalyst, [Ir(ppy)2(dtbbpy)]PF6, substoichiometric amounts of triphenylphosphine and sodium trifluoroacetate as a base. 相似文献
92.
Clément Ghiazza Moussa Ndiaye Anfal Hamdi Anis Tlili Thierry Billard 《Tetrahedron》2018,74(45):6521-6526
Herein, the direct C-5 fluoroalkylselenolation of 8-aminoquinolines is described. The Pd-catalyzed reaction is performed with the in situ generated fluoroalkylselenyl chloride and various 8-aminoquinoline amides or sulfonamides. The desired products were formed in moderate to excellent yields. 相似文献
93.
Yong-Jia Hao Xiao-Si Hu Jin-Sheng Yu Feng Zhou Ying Zhou Jian Zhou 《Tetrahedron》2018,74(52):7395-7398
Reported here is a highly efficient 1,6-conjugate addition of fluorinated silyl enol ethers to para-quinone methides, allowing facile access to a range of β,β-diaryl α-fluorinated ketones with good to high yields. Fe(OTf)3 was identified as the optimal catalyst, with the loading of 3?mol%. Notably, this represent the first 1,6-conjugate addition with fluorinated silyl enol ethers. The synthetic potential of the resulting adducts is also demonstrated. 相似文献
94.
The trifluoromethyl containing heterocycles, 2-hydroxy-4-aryl-3-(thien-2-oyl)-2-(trifluoromethyl)-3,4,7,8-tetrahydro-2H-chromen-5(6H)-one derivatives 4, were synthesized via a one-pot three-component reaction of aldehyde 1 with 1,3-cyclohexanedione 2 and 4,4,4-trifluoro-1-(thien-2-yl)butane-1,3-dione 3 in the presence of a catalytic amount of Et3N. The effect of bases and solvents on the reaction efficiency and yield was briefly investigated. Treatment of 4 with an excess amount of NH4OAc in ethanol afforded 2-trifluoromethyl-1H-quinolin-5-one derivatives 5. Refluxing of 4 with TsOH in CHCl3 gave the corresponding dehydrated products 8. 相似文献
95.
A series of partially fluorinated naphthalene, anthracene, and chrysene derivatives have been synthesized by a convenient one-pot reaction of multi-fluorinated aromatics and 1,4-dilithio-1,2,3,4-tetraaryl-1,3-butadiene that was generated in situ from the reduction of diphenylacetylene derivatives with lithium naphthalenide. 相似文献
96.
Wei Zhang 《Journal of fluorine chemistry》2008,129(10):910-919
This article presents an overview on fluorocarbon stationary phases for liquid chromatography (LC) applications. Fluorocarbons developed as alternative reverse phases have revealed previously unknown separation mechanisms and special utilities. Solvophobicity and fluorophilicity of the fluorinated phases provide enhanced selectivity for organofluorine compounds. The dual normal- and reverse-phase characteristics make fluorinated phases suitable for analysis of polar pharmaceutical and biological samples such as proteins, peptides, nucleotides, steroids, and alkaloids. Fluorinated phases for other applications including supercritical fluid chromatography (SFC), micellar electrokinetic liquid chromatography (MEKC), ion chromatography (IC), open tubular electrochromatography (OTEC), and liquid chromatography-mass spectrometry (LC-MS) are also highlighted. 相似文献
97.
UV-curable low-surface-energy fluorinated poly(urethane-acrylate)s for biomedical applications 总被引:2,自引:0,他引:2
Novel UV-curable fluorinated poly(urethane-acrylate) (FPUA) oligomers have been synthesized from 1H,1H,12H,12H-perfluoro-1,12-dodecanediol (PFDDOL), either 1,6-hexamethylene diisocyanate (HDI) or 4,4′-diphenylmethane diisocyanate (MDI), and 2-hydroxyethyl methacrylate (HEMA) for end-capping with photo-crosslinkable methacrylate groups. The fluorine content and the nature of the isocyanate were investigated to determine their effects on the physical properties, surface properties, and blood compatibilities of the polymers. The introduction of hydrophobic fluorocarbon chains led to phase separation and a low total surface energy, which reduced the adhesion of blood platelets onto the materials. The HDI-type UV-curable, fluorinated poly(urethane-acrylate) exhibited a low-surface-energy and superior blood compatibility (as determined from RIPA values). 相似文献
98.
Novel stearolic acid analogs (i.e., 9-octadecynoic acid analogs: 1a-d) containing the shorter perfluoroalkyl groups, CF3, C2F5, n-C3F7 or n-C4F9 group were synthesized. Equilibrium spreading pressures (πes) of their monolayers at the air-water interface were measured in order to demonstrate how the fluorine content has an effect on the stability of the fatty acid monolayers. As the fluorine content in stearolic acid molecule increased, its melting points was lowered indicating the solid bulk phase of stearolic acid became thermally unstable, while its monolayer stability evaluated by πe at 25 °C, dramatically increased and subsequently leveled off above a certain fluorine content. Under this condition, the replacement of at least five hydrogen atoms at the terminal hydrophobic segment in stearolic acid molecule by fluorine atoms (CF3CF2 group) was required to alter the bulk property of stearolic acid and exhibit the stabilization of monolayers, whereas further fluorination of stearolic acid had a minor effect on the monolayer stability. This behavior suggests the terminal fluorinated hydrophobic segment exclusively controls the interfacial stability of fatty acid monolayers. 相似文献
99.
Different methods of synthesis involved in the preparation of fluorinated telechelics (or ,ω-difunctional compounds) from ,ω-diiodoperfluoroalkanes for obtaining well-defined fluoropolymers are described. This review focuses on molecules in which fluorinated chains are located on the backbone and not in a lateral position. First, a bibliographical approach develops the syntheses of ,ω-diiodoperfluoroalkanes (1) either by chemical transformations of telechelic derivatives or by telomerisation of fluoroolefins with molecular iodine or diiodoperfluoroalkanes. Then, fluorotelechelics are synthesised by means of four different processes: (a) by the chemical change in the presence of metalic salts; (b) from the bismonoaddition of 1 to ω-functional unsaturated derivatives; (c) from the bis(monoethylenation) of 1 followed by difunctionalisation (e.g., nucleophilic substitution); (d) from the coupling reactions between 1 and -iodo-ω-functional reactants. Finally, this review describes how several well-defined fluoropolymers can be produced from these fluorinated telechelics. Their specific chemical, physical and thermal properties are discussed with regard to modern industrial requirements. 相似文献
100.
Richard D. Chambers Christopher Farren Graham Sandford Dmitri S. Yufit Judith A. K. Howard 《无机化学与普通化学杂志》2002,628(8):1857-1860
Free radicals derived from some alkyl substituted cyclohexanol derivatives react with hexafluoropropene to give a variety of polyfluoroalkylated adducts. Stereochemistry of the processes is discussed and remote functionalisation of the methyl group in 2‐methylcyclohexanol by an unusual intramolecular hydrogen atom transfer process is reported. 相似文献