Abstract: The invention relates to a process for the preparation of 1,1,1,2-tetrafluoroethane from 1,1,1-trifluoro-2-chloroethane and hydrogen fluoride in the gas phase, in which a catalyst containing chromium and magnesium is used which is obtainable by precipitating chromium(III) hydroxide by reacting 1 mol of a water-soluble chromium(III) salt with at least 1.5 mol of magnesium hydroxide or magnesium oxide in the presence of water, the reaction mixture is made into a paste containing chromium hydroxide and a magnesium salt, and the paste is then dried and treated with hydrogen fluoride at temperatures of 20 to 500° C.

Abstract: The invention relates to a process for the addition of HF to halogenated alkenes by reacting these with at least one hydrofluoride of the formula [B.cndot.n HF], in which B is an organic nitrogen base and n is an integer or fraction .ltoreq.4, it being intended that the reaction of perfluoroiso-butene CF.sub.2 =C(CF.sub.3).sub.2 is excluded.

Abstract: The invention relates to a process for the addition of HF to halogenated alkenes by reacting these with at least one hydrofluoride of the formula ?B.n HF!, in which B is an organic nitrogen base and n is an integer or fraction .ltoreq.4, it being intended that the reaction of perfluoroisobutene CF.sub.2 .dbd.C(CF.sub.3).sub.2 is excluded.

Abstract: Process for regenerating a fluorination catalyst The invention relates to a process for regenerating a fluorination catalyst containing chromium and magnesium after use in a fluorination reaction, in which the used catalyst is treated with a mixture comprising at least 10 mol % of HF, from 30 to 90 mol % of O.sub.2 and from 0 to 60 mol % of inert gas.

Abstract: The invention relates to a process for the work-up of a liquid complex hydrofluoride of a tertiary amine of the formula (I) ?R.sup.1 R.sup.2 R.sup.3 N.multidot.n HF!, where the radicals R.sup.1, R.sup.2 and R.sup.3 are C.sub.1 -C.sub.8 -alkyl groups which together have at least 7 carbon atoms and n is an integer or fractional number where 1.5<n<3, which, for the purpose of molecular addition of HF to a halogenated alkene, is reacted with the latter. In the reaction of the halogenated alkene with the complex amine hydrofluoride of the formula (I), the molar ratio HF:R.sup.1 R.sup.2 R.sup.3 N is allowed to fall until amine separates out as a further liquid phase, and the amine is separated off.

Abstract: The invention relates to a process for the preparation of perfluoropropionyl fluoride (II) by the isomerization of hexafluoropropene oxide (I): ##STR1## wherein the reaction medium used is a liquid complex ammonium hydrofluoride.

Abstract: The invention relates to the preparation of trifluoroacetyl fluoride by reacting trichloroacetyl chloride with anhydrous hydrogen fluoride in the gaseous phase on a catalyst which is obtainable by reacting a water-soluble chromium (III) salt with magnesium hydroxide or magnesium oxide in the presence of water, converting the reaction mixture into a paste, drying the paste and treating it with hydrogen fluoride.

Abstract: The invention relates to a process for the preparation of trichloroacetyl chloride by reaction of acetyl chloride or acetaldehyde or chlorinated derivatives thereof with chlorine in the presence of active charcoal as the catalyst.

Abstract: Process for preparing trifluoroethyl sulfur compounds from thiolates and 1-chloro-2,2,2-trifluoroethane. The invention relates to the preparation of trifluoroethyl sulfur compounds of the formula RSCH.sub.2 CF.sub.3 by reacting 1-chloro-2,2,2-trifluoroethane CH.sub.2 Cl--CF.sub.3 in a polar aprotic solvent with salts of thiols of the formula RSH, where R can be an alkyl or aryl radical or a heterocyclic radical.

Abstract: A process for preparing trifluoromethylanilines of the formula (I), ##STR1## in which R.sup.1 and R.sup.2, independently of each other, are hydrogen, halogen, (C.sub.1 -C.sub.4) alkyl, hydroxyl, alkoxy, alkylthio, carboxyl, or a nitro or cyano group, by reacting compounds of the formula (II) ##STR2## in which X.sub.1, X.sub.2 and X.sub.3 are in each case, identically or differently, halogen atoms,a is 0 or 1,Y is fluorine, chlorine or bromine, andR.sup.1 and R.sup.2 have the defined meaning, with anhydrous hydrofluoric acid, and converting the resulting aniline hydrofluorides with a base into the free amines.

Abstract: The invention relates to a process for the preparation of 2-H-heptafluoropropane, wherein hexafluoropropene is reacted with hydrogen fluoride in the presence of a weakly basic ion exchanger whose reactive centers comprise tertiary amino groups.

Abstract: Esters of .alpha.-fluoroacrylic acid are accessible by hydrolysis of an .alpha.-hydroxymethyl-.alpha.-fluoromalonic acid ester, decarboxylation and dehydration of the hydrolysis product and subsequent esterification of the resulting .alpha.-fluoroacrylic acid with an alcohol. The esters are polymerizable and are suitable for use as a starting material for preparing fluoropolymers which in turn are usable as materials for manufacturing transparent articles. The polymers are high-molecular and non-crystalline and have softening temperatures of above 100.degree. C.

Abstract: Compounds of the formula ##STR1## in which X represents hydrogen, --NO.sub.2 or --NH.sub.2 and Y represents --CH.sub.3, --COOH, --CONH.sub.2, --NH.sub.2 or --N.dbd.N--Z, in which the group --Z is ##STR2## with the proviso that if Y represents the group --N.dbd.N--Z, X is only --NO.sub.2, and if Y represents the group --CH.sub.3, X is only hydrogen, are described. A compound of the formula ##STR3## the preparation of which in a multi-stage process, in which the compounds of the general formula (I) are also obtained, is described, is preferred.The resulting 3,4'-diamino compound is suitable for the preparation of polycondensates and shaped articles, films and fibers of high heat resistance.

Abstract: A compound of the formula ##STR1## and the dianhydride thereof are prepared by air oxidation in the presence of a catalyst mixture composed of at least 2 heavy metal salts and also bromine in an acid organic medium. The compounds can be employed for the preparation of partially fluorinated polycondensates, such as polyimides, polycarboxamides, esters of polyamidecarboxylic acids, polyamides and imide-oligomers.

Abstract: Certain esters of .alpha.-fluoroacrylic acid are accessible by hydrolyzing .alpha.-hydroxymethyl .alpha.-fluoromalonic acid esters and subsequently decarboxylating the hydrolysis product. The phenyl .alpha.-fluoroacrylates which are substituted on the phenyl radical can be prepared by hydroxymethylating dimethyl .alpha.-fluoromalonate, decarboxylating and dehydrating the resuiting dimethyl .alpha.-hydroxymethyl-.alpha.-fluoromalonate and esterifying the resuiting .alpha.-fluoroacrylic acid with substituted phenols. The substituted phenyl .alpha.-fluoroacrylates are colorless liquids or colorless solids which can be polymerized. They are suitable for use as a starting material for the preparation of fluorine polymers.

Abstract: The invention relates to a process for the preparation of 1,1,1-trifluoro-2,2-dichloroethane by chlorinating 1,1,1-trifluoro-2-chloroethane, in which the chlorination is carried out under an elevated pressure. The pressure is preferably 10 to 400 bar, particularly 50 to 250 bar. If the reaction is initiated by heat, it is preferably carried out at 200.degree. to 300.degree. C. If it is initiated by a free-radical starter, the reaction is preferably carried out at 150.degree. to 250.degree. C.

Abstract: Partially fluorinated dicarboxylic acid and the acid chloride thereof, a process for its preparation and its use.The compound of the formula (I) ##STR1## and the acid chloride thereof are prepared by air oxidation in the presence of a catalyst mixture composed of the ions of cobalt, manganese and bromine in an acid organic medium. The compounds can be used for the preparation of linear polycarboxamides and polycarboxylic acid esters.

Abstract: Esters of .alpha.-fluoroacrylic acid are accessible by hydrolysis of an .alpha.-hydroxymethyl-.alpha.-fluoromalonic acid ester, decarboxylation and dehydration of the hydrolysis product and subsequent esterification of the resulting .alpha.-fluoroacrylic acid with an alcohol. The esters are polymerizable and are suitable for use as a starting material for preparing fluoropolymers which in turn are usable as materials for manufacturing transparent articles. The polymers are high-molecular and non-crystalline and have softening temperatures of above 100.degree. C.

Abstract: The invention relates to a process for the preparation of 1,1,1-trifluoro-2-chloroethane from trichloroethene and hydrogen fluoride in the gas phase. In this process a catalyst containing chromium and magnesium is used, which catalyst is obtainable by precipitating chromium(III) hydroxide by reacting 1 mole of a water-soluble chromium(III) salt with at least 1.5 mol of magnesium hydroxide or magnesium oxide in the presence of water, converting the reaction mixture into a paste containing chromium hydroxide and a magnesium salt and then drying the paste and treating it at temperatures of 20.degree. to 500.degree. C. with hydrogen fluoride.

Abstract: Partially fluorinated tetracarboxylic acid and the dianhydride thereof, a process for their preparation and their useA compound of the formula ##STR1## and the dianhydride thereof are prepared by air oxidation in the presence of a catalyst mixture composed of at least 2 heavy metal salts and also bromine in an acid organic medium. The compounds can be employed for the preparation of partially fluorinated polycondensates, such as polyimides, polycarboxamides, esters of polyamidecarboxylic acids, polyamides and imide-oligomers.