- Synthesis of (±) wine lactone and its analogues by a diels-alder approach
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A novel route to (±)-wine lactone (1) by a cis-selective kinetically controlled intramolecular Diels-Alder (IMDA) cycloaddition of the linear triene 2 is reported. The triene precursor was synthesised by TBAF-catalysed coupling of an acyl fluoride with an silyl enol ether. Four butadienyl but-3-enoates were prepared and cyclised under mild conditions to give a series of wine lactone analogues. The diastereoselectivity of the IMDA cycloadditions was determined by NMR spectroscopy and GC-MS, whereby the formation of the natural cis-configured wine lactone (1) was established. The diastereomeric IMDA transition states were optimised by using density functional theory at the B3LYP/6-31+G(d) level, and the Boltzmann populations of the electronic energies were found to correlate well with the experimentally observed diastereoselectivity.
- O'Connor, Patrick D.,Bin Kim,Brimble, Margaret A.
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- PROCESS AND DEVICE FOR PREPARING ENVIRONMENTALLY-FRIENDLY INSULATING GAS PERFLUOROALKYLNITRILE
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Provided are a process and a device for preparing environmentally-friendly insulating gas perfluoroalkylnitrile. The device comprises a first tank reactor, a second tank reactor, and a fixed bed reactor. A condensing and collecting device is provided at the top of the first tank reactor, a collecting and guiding channel at the bottom of the condensing and collecting device is connected to an inlet of a storage tank, and an outlet of the storage tank is connected to an inlet of the second tank reactor. The second tank reactor is connected to a perfluoroolefin tank. An outlet of the second tank reactor is connected to a storage gasification tank. The storage gasification tank is connected to a carrier gas tank, and an outlet of the storage gasification tank is connected to an inlet of the fixed bed reactor. The present invention starts from cyanuric chloride and perfluoropropylene, and uses two tank reactors and a fixed bed reactor to realize production with high atom economy. The preparation method has simple reaction conditions, high atom economy, low cost, and is continuous and enables scale production.
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Paragraph 0024-0025
(2020/04/24)
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- Cyanuric fluoride preparation method
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The invention discloses a cyanuric fluoride preparation method. According to the method, 1, 3, 5-trichlorine s-triazine and tetrabutylammonium fluoride are subjected to fluorination to obtain cyanuricfluoride and tetrabutylammonium chloride. Catalysts are omitted, reaction selectivity is high, yield can reach up to 95%, usage of hydrogen fluoride serving as a high-risk fluorine reagent or a largequantity of metal fluoride and addition of expensive catalysts are avoided, and the method has the advantages of simplicity in operation, mild reaction conditions, low cost and the like, and is suitable for industrial production.
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Paragraph 0025-0028; 0029-0032; 0033-0038; 0039-0048
(2018/05/07)
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- Ionic liquids as media for nucleophilic flurination
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The use of Room Temperature Ionic Liquids (RTILs) for a variety of halogen exchange (Halex) fluorination processes using alkali metal fluorides is assessed. Whilst fluorination of a range of halogenated substrates is possible in good yield, the utility of RTILs as reusable, inert media for such reactions is limited by the gradual decomposition of the RTIL in the presence of highly basic fluoride ion.
- Murray, Christopher B.,Sandford, Graham,Korn, Stewart R.
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- Improved syntheses of cyanuric fluoride and carboxylic acid fluorides
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Cyanuric fluoride (2) is one of the most popular fluorinating agents in organic chemistry. The title compound could be prepared in a 50 to 100 g scale by means of a chlorine fluorine exchange, the process was characterized by a simple preparation procedure, cheap reactants and a low time exposure. Carboxylic acids were converted into the corresponding acid fluorides 4a-g using cyanuric fluoride. A non-aqueous work-up led to high yields on synthesizing a range of functionalized acid fluorides. Wiley-VCH Verlag GmbH, 2000.
- Gross, Steffen,Laabs, Stephan,Scherrmann, Andreas,Sudau, Alexander,Zhang, Nong,Nubbemeyer, Udo
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p. 711 - 714
(2007/10/03)
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- Synthesis and use of amino acid fluorides as peptide coupling reagents
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The present invention is directed to the process of preparing a peptide comprising reacting a first amino acid or peptide with an amino acid fluoride of the formula: STR1 or the acid fluoride salts thereof wherein BLK is an N-amino protecting group AA is an amino acid residue and X is H or a protecting group useful, and the first amino and peptide have a free amino group and a blocked carboxy end.
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- Synthesis and use of amino acid fluorides as peptide coupling reagents
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A compound of the formula STR1 or the acid fluoride salts thereof wherein BLK is an N-amino protecting group or hydrogenAA is an amino acid residue andX is H or a protecting group useful as a coupling agent in peptide synthesis.
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- Process for the preparation of 2,4,6-trifluoro-1,3,5-triazine
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A process for the preparation of 2,4,6-trifluoro-1,3,5-triazine (cyanuric fluoride) in high purity and high yield at relatively low temperatures by reacting 2,4,6-trichloro-1,3,5-triazine (cyanuric fluoride [sic]) or mixed chlorinated/fluorinated 1,3,5-triazines with at least the equivalent amount of sodium fluoride, potassium fluoride or cesium fluoride or any desired mixture of these alkali metal fluorides in a dipolar aprotic solvent at temperatures from about 30° C. to about 110° C. and isolating the 2,4,6-trifluoro-1,3,5-triazine formed by distillation.
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- Photochemistry of Halogenocarbon Compounds. Part 5. Photolysis of Fluorinated 1,2,3-Triazine Derivatives
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Photolysis experiments are described on perfluoro-1,2,3-triazine (9) and its corresponding perfluoroisopropyl derivatives.A polymer was obtained from (9) but a dimer of perfluoro-2,4-di-isopropylazete (16) is obtained, from (15) quantitatively.The endo structure of the dimer is revealed by formation of a stable carbanion on addition of CsF.Trapping of the azete (16) with furan gave interconvertible 1:1 cycloaddition products.Products consistent with co-dimerisation of azetes are described.
- Chambers, Richard D.,Shepherd, Thomas,Tamura, Masayuki
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p. 975 - 981
(2007/10/02)
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- Water-soluble dyestuffs containing fibre-reactive groups of the vinylsulfone series and the fluoro-s-triazinyl-amino series
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Water-soluble fibre-reactive dyestuffs containing one or two fibre-reactive groups of the vinylsulfone series and one or two fibre-reactive groups of the fluoro-s-triazinyl-amino series. These dyestuffs can be applied on fibre materials containing hydroxy and/or carbonamide groups by known application and fixation techniques for fibre-reactive dyes to yield deep and fast dyeings on these materials.
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- Process for dyeing and printing fiber materials containing hydroxy and/or carbonamide groups with reactive dye containing both vinyl sulphonyl and fluoro-triazinyl groups
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A process for dyeing or printing fiber materials containing hydroxy and/or carbonamide groups, in which process a fiber-reactive, water-soluble dyestuff of the type defined below is applied to the fiber material and is then fixed on the fiber material at an ordinary or elevated temperature, if appropriate in the presence of agents having an alkaline reaction. This water-soluble dyestuff, which contains at least one sulfonic acid group, contains one or more groupings belonging to the group comprising the formulae (1a), (1b) and (1c) (in which Hal represents a halogen atom and A represents the acyloxy radical of a monobasic or polybasic acid) and also contains, linked to it, a 6-fluoro-1,3,5-triazin-2-ylamino radical, this monofluorotriazinylamino radical containing, in the 4-position, a substituent which is not an N-phenylamino or N-naphthylamino substituent having a group belonging to the above-mentioned formulae (1) attached to the optionally substituted phenyl radical or optionally substituted naphthyl radical, and is also not an amino substituent containing an azo group. Dyestuffs of this type can belong to a very wide variety of classes of dyestuffs and can be both metal-free dyestuffs and metal complex dyestuffs. With the aid of these dyestuffs and using alkaline agents, this dyeing process produces deep dyeings and prints which have good fastness properties on these fiber materials, even at low temperatures.
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- Process for the preparation of fluorinated s-triazines
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A process for the preparation of a fluorinated s-triazine, which comprises reacting a cyanuric halide, which contains at least one halogen other than fluorine, with hydrogen fluoride in the presence of active charcoal.
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- LES FLUORATIONS COMPAREES DES CHLOROPYRIMIDINES ET DE LA CHLORO-S-TRIAZINE
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The fluorinations of tetrachloropyrimidine, 2,4,6-trichloropyrimidine and trichloro-s-triazine were carried out in sealed tubes with KF in presence of inert gas and then compared.The fluorinated derivatives C4FxClyN2 with x + y = 4, O - were investigated and compared; the molar yields were found to be always higher than 50percent in our experimental conditions.We compare with the fluorinations of 2,4 and 4,6-dichloropyrimidine.It is possible to obtain directlyin good proportions, such fluorinated derivatives as 5-chlorotrifluoropyrimidine, trifluoropyrimidine and others.At high temperature (4OO deg C for 16h), tetrachloropyrimidine, in presence of KF, gave products of pyrolysis and condensation such as the fluorinated derivatives of C6Cl6 and C5Cl5N: C6FCl5, C6F2Cl4... or C5FCl4N, C5F2Cl3N...
- Hitzke,J.
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p. 385 - 402
(2007/10/02)
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- Heterocyclic Polyfluoro-compounds. Part 30. Perfluoroalkylation of Trifluoro-1,2,4-triazine
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Reaction of trifluoro-1,2,4-triazine with hexafluoropropene and caesium fluoride in the absence of solvent leads to successive replacement of fluorine by perfluoroisopropyl groups to give 5-mono-, 3,5- and possibly 3,6-di, and tri-substituted derivatives.Similarly, perfluoro-2-azapropene yields 5- and some 6-, 3,6-bis, and tris-perfluorodimethylamino-derivatives. Pyrolysis of trifluoro-1,2,4-triazine at 500 deg C/ 42 h yields trifluoro-1,3,5-triazine (32percent); of perfluoro(tri-isopropyl-1,2,4-triazine) at 560 deg C/ 0.26 s yields perfluorobutyronitrile and perfluoro-2,5-dimethylhex-3-yne; and of perfluoro(trisdimetylamino-1,2,4-triazine) at 620 deg C/ 2.4 s yields N,N-bis(trifluoromethyl)cyanamide and perfluorobis(dimethylamino)acetylene.
- Barlow, Michael G.,Haszeldine, Robert N.,Simon, Charles
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p. 2254 - 2257
(2007/10/02)
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- UEBER TRISHYDROFLUORIDE TERTIAERER AMINE UND IHREN EINSATZ ALS FLUORIERUNGSMITTEL
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Tertiary amine trishydrofluorides are stable complexes which are distillable in vacuo.They can be handled without hazard and do not corrode borosilicate glass.They are convenient agents therfore, in nucleophilic replacement reactions of chlorine or bromine atoms by fluorine forming homogeneous reaction mixtures often leading to higher yield under very mild conditions.Examples are given for the preparation of fluoroacetone, cyanuric fluoride, difluorophosgene, oxalyl fluoride and sulfur tetrafluoride.
- Franz, R.
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p. 423 - 434
(2007/10/02)
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