摘要:
Disclosed is a method of producing difluoromethane (HFC-32), which comprises firstly reacting methylene chloride with hydrogen fluoride in gas phase at 280 to 340null C. in the presence of a fluorinated catalyst to produce chlorofluoro methane, and secondly reacting the chlorofluoro methane with hydrogen fluoride in liquid phase at 60 to 80null C. in the presence of an antimony chloride catalyst. The method is advantageous in that HFC-32 is produced in high yield under mild reaction conditions using a relatively small amount of energy.
摘要:
A process for the production of a hydrofluoroalkane, which process comprises contacting a hydrochlorofluoroethane of formula CClXYCFHZ, wherein X and Y are each independently chlorine or fluorine and Z is chlorine, fluorine or hydrogen, in the liquid phase with hydrogen fluoride and a fluorination catalyst and recovering a hydrofluoroalkane from the resulting products.
摘要:
It is to provide a process for synthesizing an intended fluorine-containing compound having a geminal difluoro structure with a high yield, by subjecting a carbonyl compound which is readily available to a two-stage reaction. A compound (1) such as ethyl 4-oxocyclohexanecarboxylate is reacted with a compound of the formula X-Z or a compound of the formula Z2O (wherein Z is a monovalent group which gives a leaving group of the structure nullOZ, and X is a chlorine atom, a bromine atom or an iodine atom) such as phosphorus pentachloride, and then a fluorinating agent which generates fluorine anions such as HF is acted thereon to obtain a fluorine-containing compound (2) such as ethyl 4,4-difluorocyclohexanecarboxylate. 1
摘要:
1,1,1,3,3-pentafluoropropane is produced by reaction between 1,1,1,3,3-pentachloropropane and hydrogen fluoride in the presence of a hydrofluorination catalyst. The 1,1,1,3,3-pentachloropropane may advantageously be obtained by reaction between vinyl chloride and tetrachloromethane in the presence of a telomerization catalyst and of a nitrile.
摘要:
A process for production of high-purity hexafluoroethane, wherein a mixed gas containing hexafluoroethane and chlorotrifluoromethane is reacted with hydrogen fluoride in a gas phase in the presence of a fluorination catalyst at 200-450null C., for fluorination of the chlorotrifluoromethane, or wherein pentafluoroethane containing chlorine compounds with 1-3 carbon atoms is reacted with hydrogen in a gas phase in the presence of a hydrogenation catalyst at 150-400null C., and the product is then reacted with fluorine in a gas phase in the presence of a diluent gas.
摘要:
The invention relates to liquid-crystalline compounds of the formula I, 1 and to liquid-crystalline media comprising at least one compound of the formula I and to electro-optical displays containing such a liquid-crystalline medium.
摘要:
1,1-Difluoroethane containing less than 10 mg/kg of vinyl chloride is obtained by treatment, with hydrogen fluoride, of a crude 1,1-difluoroethane containing less than 1 mol of hydrogen chloride per mole of 1,1-difluoroethane.
摘要:
The present invention relates to a process for the synthesis of highly active modified carbon supported palladium catalyst by simultaneously impregnating activated carbon with a palladium precursor and an aluminium precursor. The carbon supported palladium catalyst is useful for the hydrodechlorination of dichlorodifluoromethane to produce difluoromethane.
摘要:
The present invention relates to novel solid-phase processes for the production of radiolabelled tracers, in particular for the production of 18F-labelled compounds which may be suitable for use as Positron Emission Tomography (PET) radiotracers. The invention also comprises radiopharmaceutical kits using these novel processes.
摘要:
The invention relates to a process for preparing 1,1,1-trifluoro-2,2-dichloroethane (F123). This process consists in placing 1,1,1-trifluoro-2-chloroethane (Fl33a) in contact with chlorine in the presence of hydrogen fluoride and a fluorination catalyst. F133a may be obtained by fluorination of trichloroethylene, and the F123 may be subsequently fluorinated to F125.