Abstract: The present invention relates to the compounds cis-4-(2,2,3,3-tetrafluoropropoxy)cinnamonitrile and trans-4-(2,2,3,3-tetrafluoropropoxy)cinnamonitrile and to a process for their preparation.

Abstract: The present invention relates to substituted 2-chloro-3,4,5-trifluorobenzenes of the formula ##STR1## in which R is NO.sub.2, NH.sub.2, CN or Cl, and to a process for the preparation of substituted 2-chloro-3,4,5-trifluorobenzenes of the formula given above, in which R is NO.sub.2, NH.sub.2, CN, Cl or Br, which involves reacting 2,3,4-trifluorochlorobenzene with a nitrating agent in the presence or absence of a water-insoluble solvent at from -10.degree. C. to 50.degree. C., reducing 2-chloro-3,4,5-trifluoronitrobenzene or a mixture which contains 2-chloro-3,4,5-trifluoronitrobenzene and 5-chloro-2,3,4-trifluoronitrobenzene, in the presence of an organic solvent, isolating 2-chloro-3,4,5-trifluoroaniline or a mixture which contains 2-chloro-3,4,5-trifluoroaniline and 5-chloro-2,3,4-trifluoroaniline, diazotizing this product, if desired, and exchanging the diazotized group for a chloride atom, bromide atom or cyanide radical.

Abstract: Trifluorophenylene compounds of the formula (I) ##STR1## in which ##STR2## are mesogenic radicals, are useful components for liquid-crystal mixtures.

Abstract: The present invention relates to compounds of the formula ##STR1## in which R.sup.1 and R.sup.2 are identical or different and are hydrogen or an alkyl radical having 1 to 18 carbon atoms and optionally containing oxygen, nitrogen or halogen, the radicals X, Y and Z are identical and are a fluorine, bromine or iodine atom or if two of the radicals X, Y or Z are identical or all of the radicals X, Y, Z are different from each other, X, Y and Z are a fluorine, chlorine, bromine or iodine atom. The invention further relates to a process for the preparation of the compounds, by reacting an aryldiazonium salt of the formula ##STR2## in which the radicals X, Y and Z are identical and are a fluorine, bromine or iodine atom or, if two of the radicals X, Y and Z are identical or all of the radicals X, Y, Z are different from each other, X, Y and Z are a fluorine, chlorine, bromine or iodine atom and A.sup.(-) is an anion of an acid having a pK.sub.a <7, with a compound of the formula ##STR3## in which R.sup.

Abstract: The present invention relates to a process for the preparation of 4-alkoxy-3,5,6-trifluorophthalic acids of the formula ##STR1## in which R is an alkyl radical having 1 to 5 carbon atoms which may be monofluorinated or polyfluorinated, a cycloalkyl radical having 3 to 5 carbon atoms in the ring which may be monofluorinated or polyfluorinated, or an araliphatic radical which may be monofluorinated or polyfluorinated, or, if desired, of 3-alkoxy-2,4,5-trifluorobenzoic acids of the formula ##STR2## in which R is as defined above, which involves reacting tetrafluorophthalic acid or tetrafluorophthalic anhydride with an alcohol of the formula ROH in which R is as defined above and with a water-soluble base in water at elevated temperature, isolating the 4-alkoxy-3,5,6-trifluorophthalic acid formed and, if desired, decarboxylating the 4-alkoxy-3,5,6-trifluorophthalic acid in the presence of a basic solvent and, if desired, of an inert solvent at from 70.degree. to 180.degree. C.

Abstract: A process for the preparation of halogenated benzoic acids of formula (1): ##STR1## in which R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are hydrogen, fluorine, chlorine or bromine atoms or C.sub.1 -C.sub.6 -alkyl, C.sub.1 -C.sub.6 -alkoxy, nitro, cyano, trifluoromethyl, aidehyde, C.sub.1 -C.sub.4 -alkoxycarbonyl, -SO.sub.2 -C.sub.1 -C.sub.4 -alkyl, -SO.sub.2 -phenyl, -CONH.sub.2, -CON(C.sub.1 -C.sub.4 -alkyl).sub.2, hydroxy, carboxy, -NH.sub.2 or -N(C.sub.1 -C.sub.4 - alkyl).sub.2 groups, at least one of the substituents R.sub.1 -R.sub.5 being one of said halogen atoms, which comprises reacting 1 mol of a benzophenone, asymmetrically substituted on the benzene rings A and B, of general formula (2): ##STR2## in which R.sup.1 -R.sup.10 are as defined above for R.sub.1 -R.sub.

Abstract: The present invention describes the novel intermediates 2,3-difluoro-6-nitrobenzonitrile and 2-chloro-5,6-difluorobenzonitrile, a process for their preparation and their advantageous use for the preparation of 2,3,6-trifluorobenzoic acid, which in turn is a valuable intermediate for the preparation of insecticides and antibacterial agents. The intermediates according to the invention are prepared from 2,3,4-trifluoronitrobenzene by fluorine/cyanide exchange and subsequent denitrating chlorination. 2,3,6-Trifluorobenzoic acid can be prepared from the novel intermediates, in a manner known per se in the literature, by simple chlorine/fluorine exchange and subsequent hydrolysis in a process which overall is industrially advantageous and economically favorable.

Abstract: The present invention relates to a process for the preparation of compounds of the formula ##STR1## in which R.sup.1 is --CN, --COOH, --COOR', R' being an organic radical having 1 to 6 carbon atoms, --CONH.sub.2, --COCl or --CHO and R.sup.2 is H or Cl, which comprises reacting a compound of the formula ##STR2## in which R.sup.1 is as defined above and R.sup.3 is H or Cl, with a chlorinating agent in the presence of a chlorination catalyst at -10.degree. to 200.degree. C.

Abstract: The invention relates to a novel process for the preparation of substituted 2,3-difluoropyridines by reaction of substituted 2,3-halopyridines with fluoride salts in the presence of phase transfer catalysts, preferably in polar aprotic solvents, without removing the resulting substituted 2,3-difluoropyridines continuously from the reaction mixture. The substituted 2,3-difluoropyridines which can be prepared according to the invention are, inter alia, starting materials for the preparation of plant protection agents or pharmaceuticals.

Abstract: Fluorobenzonitriles and chlorofluorobenzonitriles are prepared in an advantageous manner from the corresponding chlorobenzonitriles and an alkali metal fluoride in a chlorine-fluorine exchange reaction, by catalyzing the reaction with a quaternary ammonium compound comprising at least one alkoxypolyoxyalkyl radical.

Abstract: The present invention relates to the novel compound 4-hydroxy-2,3,5-trifluorobenzoic acid and to a process for preparing this novel substance by reacting 2,3,4,5-tetrafluorobenzoic acid at elevated temperature with a basic compound dissolved and/or suspended in water, adding, if desired, a fluoride scavenger, bringing the resulting reaction mixture to a pH of 0 to 6 by addition of an acid, and isolating the 4-hydroxy-2,3,5-trifluorobenzoic acid formed.

Abstract: The present invention relates to a process for preparing alkyl 3-hydroxy-2,4,5-trifluorobenzoate and/or alkyl 3-alkoxy-2,4,5-trifluorobenzoate by reacting 3-hydroxy-2,4,5-trifluorobenzoic acid with a dialkyl carbonate at 80.degree. to 200.degree. C.

Abstract: Process for preparing amines by reacting amides in aqueous-alkaline solutions and/or suspensions with halogens or hypohalites in the presence of alcohols, and converting the reaction products into the amines by hydrolysis, hydrogenation or reductive methods.

Abstract: The present invention relates to a process for the preparation of tetrafluorophthalic acid and/or tetrafluorophthalic anhydride by reacting a compound of the formula ##STR1## in which X is a radical ##STR2## which is optionally mono- or polysubstituted on the aromatic nucleus by fluorine and/or chlorine and/or alkyl groups having 1 to 4 carbon atoms, or is a radical ##STR3## in which R.sub.1, R.sub.2 and R.sub.3 are as defined, with water, and subsequently removing the water still present by azeotropic distillation or extracting the tetrafluorophthalic acid and/or its anhydride with a water-insoluble solvent or solvent mixture.

Abstract: Compounds of the formula ##STR1## in which X is the radical ##STR2## where R.sub.1 and R.sub.2 are in each case a hydrogen atom, an alkyl-(C.sub.1 -C.sub.10) group, aryl group, alkyl(C.sub.1 -C.sub.6)-CO group or aryl-CO group, where the aryl or aryl-CO group in the case of R.sub.1 and R.sub.2 can be substituted on the aromatic ring by fluorine and/or chlorine atoms and/or alkyl(C.sub.1 -C.sub.4) groups, or R.sub.1 and R.sub.2 together are a phthaloyl radical which can be substituted on the aromatic ring by 4 chlorine atoms or 4 fluorine atoms, or where X is the radical ##STR3## which can be substituted on the aromatic ring by fluorine and/or chlorine atoms and/or alkyl(C.sub.1 -C.sub.4) groups, and processes for their preparation.

Abstract: According to a process for producing isomer-free 2,3-difluoro-6-nitrophenol, 2,3,4-trifluoronitrobenzene is reacted with an aqueous solution of alkali metal or alkaline earth metal hydroxide in the absence of organic solvent, at temperatures between about 20.degree. C. and 100.degree. C., the pH value of the reaction mixture is set at about 1 to 6 by acid addition, the resulting product is stream distilled and the 2,3-difluoro-6-nitrophenol is isolated after cooling. No organic solvents are used during any of the steps of the process.

Abstract: Compounds of the formula ##STR1## in which X is the radical ##STR2## where R.sub.1 and R.sub.2 are in each case a hydrogen atom, an alkyl-(C.sub.1 -C.sub.10) group, aryl group, alkyl(C.sub.1 -C.sub.6)-CO group or aryl-CO group, where the aryl or aryl-CO group in the case of R.sub.1 and R.sub.2 can be substituted on the aromatic ring by fluorine and/or chlorine atoms and/or alkyl(C.sub.1 -C.sub.4) groups, or R.sub.1 and R.sub.2 together are a phthaloyl radical which can be substituted on the aromatic ring by 4 chlorine atoms or 4 fluorine atoms, or where X is the radical ##STR3## which can be substituted on the aromatic ring by fluorine and/or chlorine atoms and/or alkyl(C.sub.1 -C.sub.4) groups, and processes for their preparation.

Abstract: The present invention relates to a process for the preparation of isomerically pure 2-nitro-5-fluoro- or -5-chlorophenol, by reacting 2,4-difluoronitrobenzene or 2,4-dichloronitrobenzene with aqueous alkali metal or alkaline earth metal hydroxide solution or suspension in the absence of organic solvents or other solubility promoting substances at temperatures from about 20.degree. C. to about 190.degree. C., adjusting the pH of the reaction mixture to about 1 to about 6 by the addition of acid, steam distilling the resultant product and isolating it from the distillate after cooling.

Abstract: Process for the preparation of 2,4-dichlorofluorobenzene in high yield and purity without intermediate separation of the isomers formed,(1) by nitrating 1 mol of fluorobenzene to give nitrofluorobenzene using a mixture comprising 35 to 65 parts by weight of 50 to 90% strength sulfuric acid and 35 to 65 parts by weight of a nitrating acid comprising 35 to 55 parts by weight of 95 to 98% strength sulfuric acid and 45 to 65 parts by weight of 96 to 98% strength nitric acid, with the proviso that 0.8 to 2.0 equivalents of the nitrating agent NO.sub.2.sup.+ are used per mol of fluorobenzene, at 20.degree. to 90.degree. C., (2) allowing 25 g to 150 g of chlorine, in the presence of a ring chlorinating catalyst, to act on each 100 g of the crude nitrofluorobenzene mixture obtained, at 20.degree. to 100.degree. C.

Abstract: Process for the preparation of 3,4,6-tetrafluorophthalic acid of the formula (1) ##STR1## or the anhydride thereof in good yields and in an advantageous manner, by dehalogenating tetrafluorophthalic anhydride of the formula (2) ##STR2## or tetrafluorophthalic acid in aqueous-alkaline medium using zinc at temperatures of approximately 20.degree. C. to approximately 160.degree. C. and, if appropriate, converting the resulting 3,4,6-trifluorophthalic acid into the anhydride in a known manner by dehydrating it.