- Hexafluoropropylene oxide-alcohol: A convenient system for silica dissolution
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A new method of silica dissolution is described. It involves the formation of a stable SiF4 n ROH complex (1, 1a) just from SiO2 and anhydrous alcoholic HF generated in situ from commercially available hexafluoropropene oxide. Alcoholic SiF4 complexes can be easily converted to different organosilicon compounds of the type SiF4L 2 and (LH)2SiF6 [L = 1,10-phenantroline (2a), 2,2'-dipyridyl (2b), Me2SO (2c), pyridine (2d), triethanolamine (3a)]. Different silica-containing compounds can be used in this strategysilicagel, sand, alumosilicates, and even rice husk. Copyright Taylor & Francis Group, LLC.
- Lermontov, Sergey A.,Malkova, Alena N.,Lermontova, El'mira Kh.,Churakov, Andrei V.
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- Synthesis and catalytic activity of ruthenium complexes modified with chiral racemic per- and polyfluorooxaalkanoates
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Silver salts of racemic 2H-perfluoro(3-oxahexanoic) (3a), perfluoro(2-methyl-3-oxahexanoic) (3b) and 2,3,3,3-tetrafluoro-2-methoxypropanoic acid (3c) gave with Hoveyda-Grubbs 2nd generation catalyst 4 or its bis(polyfluoroalkylated) analogue 5 the corresponding bis(polyfluoroacylated) ruthenium complexes 1a–1c or 2a, 2b as mixtures of three diastereoisomers. Their catalytic activity in model ring-closing metathesis (RCM) reactions decreased in the order 1b–2b?>?1a–2a?>?1c due to increased steric hindrance around the catalytic centre in complexes 1a, 1c and 2a, as well as due to lower acidity of acid 3c resulting in lower electrophilicity of the complex 1c. Thus, the complexes 1b and 2b displayed high activity in RCM of bis-unsaturated malonates forming disubstituted (RCM2) or trisubstituted (RCM3) double bond and were even significantly active in the formation of tetrasubstituted bond (RCM4), while complexes 1a, 1c were active in RCM2 but inactive in RCM3. Moreover, the yield of RCM2 catalyzed with complex 1c was rather low.
- Lipovská, Pavlína,Rathouská, Lucie,?im?nek, Ond?ej,Ho?ek, Jan,Kola?íková, Viola,Rybá?ková, Markéta,Cva?ka, Josef,Svoboda, Martin,Kví?ala, Jaroslav
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- Preparation method of 2-fluoro-2-alkyloxy trifluoropropionate
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The invention discloses a preparation method of 2-fluoro-2-alkyloxy trifluoropropionate. In the presence of an organic alkali and/or an inorganic alkali, hexafluoropropylene oxide and alkyl alcohols carry out reactions to obtain corresponding 2-fluoro-2-alkyloxy trifluoropropionate. The provided method has the advantages of suitable reaction temperature, high reaction yield, good selectivity, little amount of waste solid, waste water, and waste gas, and easiness for industrialization. The prepared 2-fluoro-2-alkyloxy trifluoropropionate can be used as a trifluoromethylation reagent for the synthesis of novel medicines and pesticides.
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Paragraph 0020; 0021
(2017/08/29)
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- FIVE-MEMBERED CYCLIC ANION USE THEREOF AS AN ELECTROLYTE
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A pentacyclic anion salt is provided for use thereof in electrolyte compositions. The compound has an inorganic, organic or organometallic cation M of valency m (1≦m≦3) and m anions corresponding to the formula (I) in which Rf is a —CFZ′Z″ group in which Z′ is F or a perflouroalkyl group having from 1 to 3 carbon atoms, and Z″ is an H, F or Cl group, an optionally fluorinated or perfluorinated alkoxy group having from 1 to 5 carbon atoms, an optionally fluorinated or perfluorinated oxaalkoxy group having 1 to 5 carbon atoms or an optionally fluorinated or perfluorinated alkyl group having from 1 to 5 carbon atoms; Z″ being other than F when Z′ is F. An electrolyte composition comprises said salt in solution in a liquid solvent or a polymer solvent.
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Paragraph 0085
(2015/11/28)
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- Methyl 3,3,3-trifluoropyruvate: An improved procedure starting from hexafluoropropene-1,2-oxide; identification of byproducts
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Optimized laboratory-scale preparation of methyl 3,3,3-trifluoropyruvate (3, MTFP) has been developed starting from industrial hexafluoropropene-1,2-oxide (1, HFPO) via methyl 2,3,3,3-tetrafluoro-2-methoxypropanoate (2, MTPr), which was transformed to 3 using sulfuric acid with isolated yields up to 81%. Byproducts formed in the transformation of 2 to 3, viz. methyl trifluoroacetate (4, MTAc), methyl 3,3,3-trifluoropyruvate hydrate (5), methyl hemiacetal of trifluoropyruvate (6), a dimer of methyl 3,3,3-trifluoropyruvate hydrate (7, DimMTP), and methyl fluorosulfate (8, Sulf) were identified and their amounts determined under various experimental conditions. Potential reaction pathways leading to the formation of the byproducts are discussed.
- Dolensky, Bohumil,Kví?ala, Jaroslav,Pale?ek, Ji?í,Paleta, Old?ich
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- Synthesis of desflurane
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An improved preparation of desflurane, 1,2,2,2-tetrafluoroethyl difluoromethyl ether utilizing hexafluoropropene epoxide as a starting material. Hexafluoropropene epoxide is advantageous in that it is relatively inexpensive and is environmentally acceptable.
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- SYNTHESIS AND REACTIVITY OF POLYFLUORINATED FLUOROSULFATOCARBINOLS IN THE PRESENCE OF BASES
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Compounds CF3CR(OH)CF2OSO2F (I) (R = MeO, Ph) were synthesized by the reaction of α-(fluorosulfato)pentafluoroacetone with MeOH or C6H6/AlCl3.In the presence of bases compound (I), depending on the reaction conditions, forms either cyclic sulfates or prod
- Delyagina, N. I.,Rogovik, V. M.,Cherstkov, V. F.,Sterlin, S. R.,German, L. S.
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p. 1401 - 1405
(2007/10/02)
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- UNUSUAL REACTION CHEMISTRY IN THERMAL DECOMPOSITION OF ALKALI METAL 2-ALKOXY-2,3,3,3-TETRAFLUOROPROPIONATE SALTS
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Pyrolyses of several salts ROCF(CF3)CO2(-)M(+) (R=Me, Et, CF3CH2; M=Na, K, Cs) have been studied.The reaction chemistry shows highly unusual dependence on the nature of the alkoxy substituent and the metal cation.Product distribution are described along with some proposed mechanisms.
- Pellerite, Mark J.
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- PERFLUORINATED INTERNAL α-OXIDES IN REACTION WITH SODIUM METHOXIDE
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Perfluorinated internal α-oxides interact with sodium methoxide in methanol, giving the products from "haloform" dissociation of the intermediately formed α-methoxy-perfluoro ketones.In unsymmetrical disubstituted perfluorinated internal α-oxides nucleophilic attack by the methoxide ion is directed at both carbon atoms of the epoxide ring, while the trisubstituted perfluorinated α-oxides from the products from regiospecyfic opening of the ring.The stability of the α-oxides to the action of sodium methoxide increases with increase in the size of the perfluoroalkyl substituents in the epoxide ring.
- Zapevalov, A. Ya.,Filyakova, T. I.,Peschanskii, N. V.,Kodess, M. I.,Kolenko, I. P.
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p. 441 - 445
(2007/10/02)
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