Abstract: The invention concerns 4,6-diamino-resorcinol which is prepared in the form of its dihydrochloride by catalytic hydrogenation of 1,3-benzyloxy-4,6-dinitrobenzene on a noble metal contact in a two-phase mixture of dilute aqueous hydrochloric acid and an organic solvent which is not miscible with dilute aqueous hydrochloric acid. This process is carried out at a pressure of between 1 and 200 bar and a temperature of between 0 and 200.degree. C.

Abstract: Process for the preparation of alkyl aryl ethers containing carboxyl groups which are suitable for the preparation of colour film couplers, or derivatives thereof, by reaction of aromatic alcohols with alkyl halides containing carboxyl groups or derivatives thereof and basic alkali metal or alkaline earth metal compounds, characterized in that the reaction is carried out in the melt of the aromatic alcohol.

Abstract: Process for preparing haloaromatic amines by catalytic hydrogenation of the corresponding halonitroaromatic compounds, characterized in that iron-containing Raney nickel is used as catalyst, where the haloaromatic amines prepared can be used for the synthesis of photographic couplers which are useful in photographic emulsions or elements.

Abstract: Mononitrohalogenobenzenes can be prepared by mixing halogenobenzene, nitric acid, sulphuric acid and water intensively with one another, simultaneously or in succession in their total quantity, and by redispersing them at least twice in the case of continuous preparation, applying a mixing energy of 1-40 watts per liter of the overall reaction mixture, preferably 3-30 W/l, largely suppressing back-mixing in the continuous procedure, and observing adiabatic reaction conditions.

Abstract: Mononitrotoluenes can be prepared by intensively mixing together toluene, nitric acid, sulphuric acid and water, simultaneously or successively in their total amount, and, in the case of continuous preparation, redispersing the mixture at least twice, for which purpose a mixing energy of 1 to 40 watts per liter of the total reaction mixture, preferably 3 to 30 W/l, is employed per volume of the reactor, and, for the continuous procedure, the back mixing is substantially repressed. Adiabatic reaction conditions are maintained.

Abstract: 4,6-diaminoresorcinol can be prepared in a plurality of steps in such a way thata) 1,3-dichlorobenzene is nitrated with a mixed acid of HNO.sub.3, H.sub.2 SO.sub.4 and SO.sub.3 at 0 to 40.degree. C. in anhydrous H.sub.2 SO.sub.4,b) the resulting 1,3-dichloro-4,6/2,4-dinitrobenzene isomeric mixture is first reacted with benzyl alcohol in the presence of a strong base at -15.degree. C. to +15.degree. C. and then at 20.degree. to 40.degree. C. to give the dibenzyloxy compound andc) the 1,3-dibenzyloxy-4,6-dinitrobenzene isomer arising in pure form in b) is converted to the 4,6-diaminoresorcinol by catalytic hydrogenation.

Abstract: p-Amino-phenols are advantageously prepared by catalytic hydrogenation of the aromatic nitro compounds on which they are based in a reaction medium of aqueous sulphuric acid in the sense of a Bamberger rearrangement at elevated temperature by a procedure in which the reaction medium additionally contains a water-miscible organic solvent.

Abstract: .beta.-Aminoacrylic acid esters can be prepared by reacting acetic acid esters of the formulaH.sub.2 CR.sub.1 --COOR.sup.2 (II)with aminal esters of the formula ##STR1## at 0.5-10 bar and 50.degree.-170.degree. C. in an aprotic polar solvent. The radicals R.sup.1 to R.sup.7 are as defined in the description.

Abstract: Dinitro-polyalkylbenzenes can be prepared by nitration of polyalkylbenzenes using HNO.sub.3 in the presence of H.sub.2 SO.sub.4 in such a manner that at least 50% of the H.sub.2 SO.sub.4 is present as reaction medium and HNO.sub.3 and the polyalkylbenzene and any remaining H.sub.2 SO.sub.4 are added simultaneously in such a manner that the added substances polyalkylbenzene and HNO.sub.3 are in the molar ratio of 1:2-10. H.sub.2 SO.sub.4 is used at a concentration from 81 to 96% by weight and HNO.sub.3 at a concentration from 95 to 100% by weight. For the work-up, the dinitro-polyalkylbenzenes are first freed from the majority of the acids and then treated with a highly dilute aqueous solution of a dispersant for separating off residual acid.

Abstract: Ortho-amides of the formula ##STR1## can be prepared by reacting salts of the formula ##STR2## with alcoholates of the formulaM.sup.1 OR.sup.1 (III)where the radicals R.sup.1 to R.sup.4, M.sup.1 and X.sup..crclbar. have the meaning given in the description. The alcoholates are employed in highly active form with an effective content of 98-100% M.sup.1 OR.sup.1.

Abstract: N-acylated p-amino-phenols can be prepared by catalytical hydrogenation of the underlying aromatic nitro compounds in a reaction medium of aqueous sulfuric acid in the sense of a Bamberger type reaction at elevated temperature, optionally in the presence of a water-miscible organic solvent, and subsequent reaction of this reaction mixture with an acid chloride, optionally in the presence of an acid binder and optionally in the presence of a diluent.

Abstract: Dialkyl carbonates can be prepared by reaction of carbon monoxide with alkyl nitrites in a continuous gas phase reaction, in which a platinum metal catalyst of oxidic or hydroxidic compounds of elements from group Vb of the Periodic Table (Mendeleev) as supports and, if desired, addition of an antimony, bismuth, aluminium, copper, vanadium, niobium, tantalum, tin, iron, cobalt, nickel compound or a mixture of a plurality thereof on this catalyst are used, and the hydrogen halide which is discharged from the reactor together with the reaction mixture is batchwise or continuously replaced in the course of the reaction. This results in the formation of dialkyl carbonates in almost quantitative selectivity; the corresponding dialkyl oxalates can, in most cases, not be detected.

Abstract: When 2-naphthylamine-1,5-disulphonic acid is precipitated from the as-sulphonated reaction mixtures by dilution, a purer product is obtained, with a low level of adherent sulphuric acid, if the precipitation by dilution of the reaction mixture is carried out under precisely defined conditions.

Abstract: Aminomethylene compounds of the formula ##STR1## can be prepared by reaction of C-H-acid compounds of the formula ##STR2## with salts of the formula ##STR3## in the presence of simple inorganic bases, where the radicals R.sup.1 to R.sup.4, R.sup.7, R.sup.8 and X.sup..crclbar. have the meanings given in the description.

Abstract: Pure or substantially enriched 2,4- and 2,6-dinitrotoluene can be isolated from a mixture containing these isomers if such a mixture is distilled under a pressure of 0.5 to 20 mbar at a temperature of 80.degree. to 200.degree. C. with exclusion of reducing conditions.

Abstract: Crude 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)propane (=tetramethyl-bisphenol A=TMBPA) can be purified by recrystallization, if C.sub.1 -C.sub.4 -monoalcohols with a water content of 2 to 40% by weight relative to the total weight of alcohol and water are used in an amount of 70 to 250% by weight, relative to the amount of TMBPA and the recrystallization is carried out at a temperature of 65.degree. to 150.degree. C.

Abstract: Thermotropic, fully aromatic polyesters based on p-hydroxybenzoic acid, aromatic dicarboxylic acid and diphenol in which the dicarboxylic acid groups consist at least in part of 3,3'-diphenyldicarboxylic acid groups have excellent mechanical properties, in particular excellent elongation at break.

Abstract: The process for the preparation of N-methylolcaprolactam through reaction of caprolactam with formaldehyde in the presence of an alkaline catalyst at elevated temperature is essentially improved when the reaction is carried out substantially solvent-free at 70.degree. to 100.degree. C. In an advantageous fashion, the alkaline catalyst used is in heterogeneous form. In a furthermore advantageous fashion, seed crystals of pure N-methylolcaprolactam are added to the reaction batch after cooling to a temperature below the melting point of pure N-methylol-caprolactam.

Abstract: 1-Amino-naphthalene-7-sulphonic acid is prepared by reacting 1-chloro-naphthalene-4,7-disulphonic acid with ammonia at elevated temperatures in the presence of water and optionally in the presence of a catalyst such as a copper catalyst.

Abstract: 1,5- AND 1,8-DINITRONAPHTHALENES ARE ISOLATED FROM MIXTURES OF ISOMETRIC DINITRONAPHTHALENES AT LEAST CONTAINING THE SAME. The mixture of isomers is treated successively with a more polar solvent and a less polar aromatic solvent for dinitronaphthalenes thereby dissolving the mixture of isomers except for 1,5-dinitronaphthalenes which remains largely undissolved in the more polar solvent. The residual mixture of isomers is subsequently treated, after removal of the more polar solvent, with a less polar aromatic solvent at elevated temperatures in which 1,8-dinitronaphthalenes remains as a largely insoluble residue.