The way to obtain 1,1,1,2-tetrafluoroethane
(57) Abstract:Usage: 1,1,1,2-Tetrafluoroethane is used as a solvent, as a refrigerant. Conditions of synthesis: the reaction of HF and trichloroethylene in the presence of a catalyst, resulting in a mixture containing 2-chloro-1,1,1-Cryptor-ethane and 1,1,1,2-Tetrafluoroethane, and optionally other organic by-products. The reaction proceeds in a single reaction zone by extraction 1,2,1,2-Tetrafluoroethane from a mixture and return to the recycling 2-2-chloro-1,1,1-triptorelin, and optionally, other organic by-products from the reaction mixture, together with trichloroethylene and HF. HF take in a molar ratio of 3 to 30 times the molar quantity of trichloroethylene, as the catalyst used is a salt of metal selected from chromium salts, cobalt salts on the media-aluminum fluoride, fluorinated aluminum oxide or coal. 1 C.p. f-crystals, 2 tab. The invention relates to an improved method of producing 1,1,1,2-Tetrafluoroethane (HFC-134a) by catalytic reaction of trichloroethylene with HF, in which the reaction proceeds in a single reaction zone to return to the recycling of 2-chloro-1,1,1-triptorelin (HCFC-a) with trichloroethylene in the reaction zone.Known UB>2Y is Br, Cl, F, and Y is chlorine, HF. The interaction is carried out in the vapor phase at elevated temperatures (300-400aboutC). As the catalyst used chromium oxide or which is at least partly is a basic chromium fluoride. HF is passed directly over the catalyst at a temperature within 100-275about
Closest to the proposed method is a way to obtain 1,1,1,2-Tetrafluoroethane by reacting HF with trichloroethylene at an elevated temperature in the presence of catalyst 3-valent chromium compounds. The target product is obtained with a low output 
The aim of the invention is to increase the yield of the target product in the implementation process in the same reaction zone.This goal is achieved by the fact that this method lies in the fact that conduct the interaction of HF with trichloroethylene at 300-425aboutIn the presence of a catalyst metal salt, with the formation of a mixture containing 2-chloro-1,1,1-trifluoroethane and 1,1,1,2-Tetrafluoroethane, and the reaction of lead in a single reaction zone, while extract 1,1,1,2-Tetrafluoroethane from the reaction mixture and recycle 2-chloro-1,1,1-trifluoroethane from the reaction mixture together with trichloroethylene is aftrican, with HF, adding advanced in a molar ratio of 3 to 30 times the molar quantity of trichloroethylene, using as a catalyst a salt of chromium, cobalt salts on the media-aluminum fluoride, fluorinated aluminum oxide or coal.Moreover, the amount of metal in the calculation of the pure metal in the catalyst composition ranges from 0.02 to 50 wt. from the catalytic composition, and the reaction is carried out in the presence of oxygen.Usually when using this catalyst composition, the higher the temperature, the greater the molar ratio HF/trichloroethylene, and the longer the duration of contact, the greater the degree of conversion in the fluorinated products and the more intensive is the formation of polyfluorinated products. During implementation of the invention can be achieved by a balance of these parameters, one against another, so that increases up to a maximum formation of CF3CH2F and decreases to a minimum the formation of more highly fluorinated CF3CHF2.The reaction of trichloroethylene with HF may be carried out in any suitable reactor, including a reactor with a fixed catalyst bed and the reactor with a fluidized bed of sloreta hydrogen, such as alloy Inconel and alloy Hastelloy.Pressure is not critical. Most suitably atmospheric and surfmaster pressure, and therefore, they are most preferred.P R I m e R s. In the examples all parts are massive and all percentages are molar and all temperatures are in degrees Celsius unless otherwise stated. Ox all reactions used in industrial HF, containing only trace amounts of water.The General procedure for fluorination.Reactor (internal diameter of 12.7 mm, length 305 mm) loaded catalyst in amounts specified in the following examples, and placed in a sand bath. This bath is slowly heated to 400aboutWith the transmission of gaseous N2a flow rate of 50 cm3/min through the reactor to remove traces of water. The temperature is reduced to 200aboutWith and gaseous HF and N2(in a molar ratio of 1/4) are passed through the reactor, and the flow rate of N2decreases with time as long as the reactor will not be only pure HF. At this point, the temperature is gradually increased to 425aboutWith and is maintained at this level for 15-300 oresti flows adjusted to achieve the above molar ratio, and time of contact, as given in the examples.A sample of the product leaving the reactor taken along the line of the stream for chromatographic analysis on a Hewlett Packard HP 5890 using the chromatographic column length (between 6.08 mm) and diameter (3.2 mm), filled with fully fluorinated polyester Krytox inert carrier and a helium flow of 35 cm3/min. Conditions in the chromatograph of the following: temperature 70aboutC for 3 min, followed programmed to increase the temperature to 180aboutWith heating rate of 6aboutC/minP R I m e R 1. The fluorination of trichloroethylene recycle HCFC-a.The fluorination is carried out with the use 19,0 g (30 ml) CoCl2/Al2O3(2% Co) as the initial mass of the catalyst. The molar ratio HF/a/trichloroethylene/ABOUT2is 10/1/0,2/0,2. The flow of the product resulting from the reaction of HF to HCFC-a, trichloroethylene and air formed over the catalyst at the time of contact with the catalyst for 20 s at 390aboutWith, and after 53 hours of work get the following results:
17.4% OF CF3CH2F (HFC-134a), 80.8% of CF3CH2Cl (HCFC-133a),
1.2% OF CF2=CHCl (FC-1122), 0,3% C
FIELD: industrial organic synthesis.
SUBSTANCE: invention relates to preparation of alkylaromatic intermediates including perfluorinated carbon atom utilized in production of agrochemically important active compounds. Intermediates simultaneously containing aniline function are obtained from homocyclic arylcarbamoyl fluoride including at least one perhalogenated carbon atom preferably bearing at least two halogen atoms capable of being replaced by fluorine atoms when in liquid-phase contact with hydrofluoric acid and water. During this reaction, molar ratio of hydrofluoric acid to arylcarbamoyl fluoride is maintained equal to 4, preferably to 5 and not higher than 11. Water is added to reaction mixture (at 10 to 90°C) when only one exchangeable halogen atom remains unreplaced. Arylcarbamoyl fluoride is obtained in situ by adding corresponding isocyanate to liquid hydrofluoric acid at temperature not exceeding 10°C. Process is carried out continuously in two reactors, the first one serving for halogen exchange reaction and the second for addition of water. Temperature 40°C is maintained until only one exchangeable halogen atom remains unreplaced.
EFFECT: increased yield and improved quality of desired product and economical characteristics.
9 cl, 4 ex
FIELD: organic chemistry, in particular difluorochloromethane useful as cooling agent, propellant, blowing agent, as well as in fluoromonomers production.
SUBSTANCE: chloroform is treated with hydrogen fluoride in presence of catalyst predissolved in chloroform with concentration of 20-30 mol.% and chlorine, at temperature of 60-110°C and pressure of 7013 atm. As catalyst mixture of antimony pentachloride, fluorotetrachloride and trichloride in ratio of 1:(0.03-0.15):(0.03-0.15), respectively is used. Process is carried out under continuous controlling reaction mass electrical resistance which is maintained in limits of 600-1600 Om. Chlorine is introduced in amount of 0.01-0.3 mass % with respect to chloroform. Method of present invention makes it possible to control synthesis parameters in dependence of reaction mass electrical resistance.
EFFECT: increased process selectivity; new catalyst.
5 cl, 4 ex
FIELD: organic chemistry.
SUBSTANCE: claimed method includes interaction of mixture C3-C6-hydrofluoroalkane/hydrogen fluoride in absence of catalyst with at least one chloro-containing or cloro- and fluoro-containing organic compound reactive towards hydrogen fluoride in liquid phase. Hydrofluoroalkane is obtained by interaction of at least one chloro-containing or cloro- and fluoro-containing precursor with hydrogen fluoride in the first step. In one of the next steps at least part of products from the first step is made to react with hydrogen fluoride, wherein one step includes separation method. Also disclosed are azeotrope or pseudo-azeotrope composition applicable for 1,1,1,3,3-pentafluorobutane purification. Claimed composition contains as main components 1.5-27.5 mol.% of 1,1,1,3,3-pentafluorobutane and 72.5-98.5 mol.% of hydrogen fluoride.
EFFECT: method with optimized parameters.
16 cl, 4 dwg, 1 tbl, 5 ex
FIELD: chemical industry; method of production of the fluorine-containing compounds.
SUBSTANCE: the invention is pertaining to the chemical industry, in particular, to the improved method of production of fluorine-containing compounds from the halogen-containing, compounds, preferably, from chlorine-containing compounds due to an exchange of halogen for fluorine at presence of the HF-additional compound of the mono- or bicyclic amine with at least two atoms of nitrogen. At that at least one atom of nitrogen is built in the cyclic system as the fluorating agent; or at presence of anhydrous hydrogen fluoride - as the fluorating agent and the indicated HF-additional compound of the mono- or bicyclic amine as the catalyst. At usage of the applicable solvents the reaction mixtures can be divided into two phases and thus to simplify the reprocessing of the products. The invention also is pertaining to the HF-additional compounds of 1.5-diazabicyclo[4.3.0]non-5-en and N,N-dialkylaminopiridin, where alkyl represents C1-C4alkyl and where the molar ratio of HF to amine makes 1:1, and to HF- additional compounds 1.8- diazabicyclo[5.4.0]undecyl-7-ene, where the molar ratio of HF to amine compounds more than 1:1.
EFFECT: the invention ensures at usage of the applicable solvents to divide the reaction mixture into two phases and thus to simplify reprocessing of the products.
17 cl, 13 ex
FIELD: organic chemistry, chemical technology.
SUBSTANCE: invention relates to an improved solid-phase method for synthesis of radioisotope indicators, in particular, for synthesis of compounds labeled with 18F that can be used as radioactive indicators for positron- emission tomography (PET). In particular, invention relates to a method for synthesis of indicator labeled with 18F that involves treatment of a precursor fixed on resin if the formula (I): SOLID CARRIER-LINKER-X-INDICATOR wherein X means a group promoting to nucleophilic substitution by a definite center of a fixed INDICATOR with 18F- ion for preparing a labeled indicator of the formula (II): 18F-INDICATOR; to compound of the formula (Ib):
and compound of the formula (Ih): ;
to radiopharmaceutical set of reagents for preparing indicator labeled with 18F for using in PET; to a cartridge for radiopharmaceutical set of reagents for preparing indicator labeled with 18F for using in positron-emission tomography.
EFFECT: improved method of synthesis.
13 cl, 1 sch, 3 ex
FIELD: isomerization and disproportionation catalysts.
SUBSTANCE: invention relates to crystalline α-chromium oxide, chromium-containing catalytic compositions, methods for preparation thereof, and to a process of fluorine distribution in hydrocarbon and/or halogenated hydrocarbon in presence of indicated catalytic compositions. Claimed crystalline α-chromium oxide, wherein about 0.05 to about 6 atomic % chromium in the lattice of α-chromium oxide is substituted by trivalent cobalt (Co+3) atoms is via coprecipitation of solid substance by introducing ammonium hydroxide, this method being supplemented by introducing an excess of ammonium nitrate into precipitated mixture before dehydration step and calcination step at 375 to 1000°C in presence of oxygen. Chromium-containing catalytic compositions containing crystalline cobalt-substituted α-chromium oxide as chromium-containing component optionally treated with fluorination agent are also claimed. Composition preparation procedure comprises: (a) coprecipitation of solid substance by introducing ammonium hydroxide into aqueous solution of soluble cobalt salt and soluble trivalent chromium salt, wherein solution contains at least three moles nitrate per mole chromium and has concentration of cobalt from about 0.05 to about 6 mol % based on total content of cobalt and chromium in solution, followed by introducing into solution at least three moles ammonium per mole chromium; (b) collecting coprecipitated solid substance obtained in step (a); (c) drying collected solid substance; and (d) calcination of dried solid substance at 375 to 1000°C in presence of oxygen.
EFFECT: increased activity of catalytic composition in above-indicated processes.
15 cl, 8 dwg, 13 ex