Abstract: Catalyst for halogen-fluorine exchange reactions on aromatics, consisting essentially of a mixture of one or more compounds of the component a) plus at least one compound of the components b), c) and/or d), whereina) is an amidophosphonium salt of the formula (I) ##STR1## where A.sup.1, A.sup.2, A.sup.3, A.sup.4, A.sup.5, A.sup.6, A.sup.7, A.sup.8 are, independently of one another, identical or different and are each a straight-chain or branched alkyl or alkenyl having from 1 to 12 carbon atoms, cycloalkyl having from 4 to 8 carbon atoms, an aryl having from 6 to 12 carbon atoms, an aralkyl having from 7 to 12 carbon atoms, or A.sup.1 A.sup.2, A.sup.3 A.sup.4, A.sup.5 A.sup.6, A.sup.7 A.sup.8 are, independently of one another, identical or different and are in each case connected to one another either directly or via O or N--A.sup.9 to form a ring having from 3 to 7 ring atoms, A.sup.9 is an alkyl having from 1 to 4 carbon atoms and B.sup..crclbar.

Abstract: A process for the preparation of N-carboxyalkyl-3-fluoro-4-dialkylaminoanilines, which comprises reacting, in a first step, 2-chloro-4,5-difluoronitrobenzene of the formula (I) ##STR1## with a secondary amine of the formula (II) HNR.sup.1 R.sup.2, in which R.sup.1 and R.sup.2, independently of one another, are identical or different and are an alkyl radical having from 1 to 10 carbon atoms or, together with the N atom to which they are bonded, form a ring having from 5 to 7 members, in the presence of a water-soluble amine which forms hydrofluorides and hydrochlorides which are liquid at the reaction temperature and work-up temperature or soluble in the reaction mixture, in the presence or absence of a solvent at -10 to 120.degree. C., reducing, in a second step, the reaction mixture containing the 2-chloro-4-dialkylamino-5-fluoronitrobenzene using hydrogen at from 30 to 150.degree. C.

Abstract: The present invention relates to a process for the preparation of compounds of the formula ##STR1## in which the radicals R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are identical or different and are COOH, H, F, Cl, Br, CF.sub.3, OH, an alkoxy or alkyl radical having in each case 1 to 4 carbon atoms or a radical --NR.sup.6 R.sup.7, in which R.sup.6 and R.sup.7 are identical or different and are H, an alkyl radical having 1 to 4 carbon atoms or a phenyl radical, by dissolving in water a compound of the formula ##STR2## in which the radicals R.sup.1, R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are identical or different and have the abovementioned meaning or, in departure therefrom, instead of H can be COOH, admixing the aqueous solution with a water-insoluble amine which is inert under the reaction conditions and carrying out the decarboxylation at a pH of 3 to 9 and a temperature of 70.degree. to 210.degree. C.

Abstract: A process for the preparation of tetrachloro-1,4-benzoquinone of high purity by the action of chlorine and concentrated hydrochloric acid on hydroquinone, by introducing a part of the hydroquinone to be employed into an initially introduced 4- to 6-fold molar amount--based on the total amount of hydroquinone--of 20 to 37 % aqueous hydrochloric acid containing catalytic amounts of iron(III) ions and an anionic dispersant, introducing 1.5 to 2.0 times the molar amount--based on total hydroquinone--of chlorine as a gas into this solution at a temperature of 20.degree. to 90.degree. C., then adding the residual amount of hydroquinone as a solid or in dissolved form, introducing 1.5 to 2.0 times the molar amount of chlorine as a gas, keeping the concentration of the hydrochloric acid here at 23-25% by addition of water and finally raising the temperature to 100.degree. to 107.degree. C. with further introduction of chlorine as a gas (1.7 to 2.

Abstract: Process for producing 1,4-bis-(4-fluorbenzoyl)-benzol by reacting terephthaloyl chloride with fluorbenzol in the presence of aluminium chloride or aluminium bromide, characterized in that aluminium chloride or aluminium bromide is added in metered quantities to a mixture of terephthaloyl chloride and fluorbenzol at temperatures of approximately 25.degree. C. to approximately 68.degree. C. and the mixture is allowed to react at said temperatures.

Abstract: The reduction of wear at the cylinder walls of combustion engines is achieved by a new type of piston with special channels and facilities for collecting lubricants and distributing the lubricants during the piston movement and especially during the first cycles onto areas of highest wear of the cylinder wall.

Abstract: An internal combustion engine with extended power stroke and shortened compression stroke has an improved efficiency over internal combustion engines having strokes of equal length.

Abstract: The invention provides a process for the preparation of p-nitrophenetole with high yields and in an especially pure form from p-chloronitrobenzene and ethanol by heating to a temperature of from 60.degree. to 80.degree. C. with addition of alkali metal hydroxide and a phase transfer catalyst.

Abstract: Crude 3,4,3',4'-tetraaminodiphenyl (TAD) prepared by ammonolysis of 3,3'-dichlorobenzidine in the presence of mainly Cu catalysts is purified by a process in which(a) after its isolation from the preparation process crude TAD is treated with an aqueous NH.sub.3 solution and, if desired, TAD thus treated is then(b) dissolved and reprecipitated in water in the presence of adsorbents and also of a water-soluble reducing agent.Compared with relevant processes of the state of the art, the process produces a higher yield of pure TAD and it is also simpler to carry out.

Abstract: Toluene is nitrated with nitric acid in the gaseous phase under reduced pressure and at temperatures from about 80.degree. - 180.degree. C, while using an acidic inorganic catalyst consisting of a carrier substance based on SiO.sub.2 and/or Al.sub.2 O.sub.3 impregnated with a high boiling inorganic acid such as H.sub.2 SO.sub.4 or H.sub.3 PO.sub.4 and optionally with metal salts of such acids. This process yields essentially p-nitrotoluene, in addition to a smaller quantity of o-nitrotoluene and a very small amount of m-isomer. The technology of the process is simple and provides good yields. The nitrotoluenes, especially the p,nitrotoluene are interesting intermediates, for example for the manufacture of dyestuffs.