Bayer Aktiengesellschaft

Haarmann & Reimer Gmbh

Bayeraktiengesellschaft

Helmut Fiege

Karlfried Wedemeyer

Franz-Josef Mais

Ferdinand Hagedorn

Albert Schnatterer

Josef Kasbauer

Wolfgang Eymann

Horst Behre

Kurt Bauer

Reiner Molleken

Guido Steffan

Alfons Klein

Klaus-Christian Paetz

Wolfram Kissener

Michael Pies

Heinz U Blank

Stefan Antons

Bernhard Beitzke

Joachim Komoschinski

Gunter Rauchschwalbe

Josef Haydn

Johann Renner

Reinhard Lantzsch

Dieter Arlt

Manfred Jautelat

Winfried Joentgen

Lothar Puppe

Heinrich Schrage

Helmut Kraus

Wolfgang Kiel

Friedrich-Wilhelm Ullrich

Rudolf Kron

Kai Rohlk

Werner Bussmann

Karl Heinz Neumann

Karl-Heinz Neumann

Dieter Heitkamp

Fritz Maurer

Alexander Klausener

Hans-Joachim Traenckner

Eberhard Zirngiebl

Joachim Franke

Heinz-Ulrich Blank

Otto Neuner

Erich Hammerschmidt

Werner Jeblick

Herbert Schmidt

Friedrich Durholz

Joerg-Dietrich Jentsch

Dieter W Bruck

Alfred Krempel

Thomas Essert

Karl-Wilhelm Henneke

Frank Arndt

Feliks Bitners

Helmut Lahr

Uwe Heinz

Wolfram Eichinger

Rudolf Helm

Herbert Muller

Rudolf Wiemers

Hartmut Richter

Wolf Mehl

Frank Jelitto

Gebhard Merz

Robert So/ Llner

Dieter Brueck

Karl-Heinz Theisen

Peter Skornia

Heinz-Gerd Hartges

The invention relates to a particularly advantageous method for producing aryl thiols through the catalytic hydrogenation of diaryldisulphides. According to the invention, the hydrogenation is carried out in a basic alcoholic medium.

Method for producing aryl thiols by hydrogenating diaryldisulphides

2-Halogenoindan-1-ones are prepared in an advantageous manner by converting anilines into diazonium salts and these, with acrylic compounds, into 3-phenyl-1-halogenoproprionic acid derivatives, and latter are cyclized.

Process for preparing 2-halogenated indan-1-ones

In a particularly advantageous process for producing 2-cyanoindan-1-ones from 2-halogenated indan-1-ones by reaction with a cyanide salt, the cyanide salt is dissolved in a dipolar aprotic solvent or in a water-miscible ether and 2-halogenated indan-1-one is metered into this solution.

Process for preparing 2-cyanoindan-1-ones

The invention relates to novel S-(4-biphenyl)-thiosulfuric acids and their salts, to a method for producing them from S-(4-biphenyl)-thiosulfinic acids and their salts, and to a method for producing 4-mercaptobiphenyls from the S-(4-biphenyl)-thiosulfuric acids and their salts.

S-(4-biphenyl)-thiosulphuric acids and their salts, method for producing the same and method for producing 4-mercaptobiphenyls

N-Phenyl-1-naphthylamine can be prepared by reaction of aniline and 1-naphthylamine in the liquid phase at 100-400.degree. C. under normal pressure, a catalyst mixture comprising boron and fluorine being employed. Such catalyst mixtures can be obtained, for example, by reaction of hydrogen fluoride, boric acid and aniline and/or 1-naphthylamine. The catalyst is recovered and can be employed again. The reaction can be carried out discontinuously or continuously.

Preparation of N-phenyl-1-naphthylamine

Process for preparing 4,6-diamino-resorcinol dihydrochloride

Particularly pure di-C.sub.1 -C.sub.4 -alkyl 5-nitro-isophthalates are obtained in good yield and in a simple process by dissolving 5-nitro-isophthalic acid in a mixture of a C.sub.1 -C.sub.4 -alkyl alcohol and a solvent which is miscible or only partially miscible with water, heating in the presence of a strong acid, thus forming a second, aqueous phase, crystallizing out, after the esterification reaction has ended, the di-C.sub.1 -C.sub.4 -alkyl 5-nitro-isophthalate formed from the organic phase by cooling and removing the aqueous phase before or after the di-C.sub.1 -C.sub.4 -alkyl 5-nitro-isophthalate is separated off.

Process for preparing di-C.sub.1 - C.sub.4 -alkyl 5-nitro-isophthalates

Non-explosive preparations of 1-hydroxybenzotriazole

N-aryl-N'-alkyl-piperazines are obtained in a particularly simple manner, in good yields and in short reaction times when an aniline is reacted under pressure with an N-alkyl-bishydroxyethyl-amine in the presence of a strong acid.

Process for preparing N-aryl-N'-alkyl-piperazines

Impure POCl.sub.3 is purified by distillation in the presence of high-boiling nitrogen compounds from the group consisting of the substituted pyridines and pyrimidines, the open-chain and cyclic aliphatic amines, the open-chain and cyclic amidines, the guanidines and the aromatic amines.

Process for the purification of phosphorus oxychloride

Halogenated aromatic carboxylic acids are decarboxylated by heating them in the presence of water at temperatures of 80.degree. to 180.degree. C. and in the presence of water and other acids at temperatures above 80.degree. C.

Process for decarboxylation of halogenated aromatic carboxylic acids

2-Amino-6-chlorophenyl-alkylsulfanes are prepared in a particularly advantageous manner by hydrogenating 2-chloro-6-nitrophenyl-alkylsulfanes catalytically in the presence of a solvent without the addition of a further sulfur compound, and the novel compound 2-amino-6-chlorophenyl-isopropylsulfane is provided.

Process for the preparation of 2-amino-6-chlorophenyl-alkylsulfanes, and

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.

Process for the preparation of alkyl aryl ethers containing carboxyl

Hydroxypivalic acid is obtained from aqueous solutions by removal of the water by azeotropic distillation and subsequent crystallization from a solvent mixture which is composed of a polar and a non-polar component. The distillation is carried out under reduced pressure and at a maximum bottom temperature of 90.degree. C., until a residual water content of at least 0.1% of the total weight of the resulting solution is achieved.

Process for isolating hydroxypivalic acid from aqueous solution

2-Chloro-4-methylphenol is prepared by reacting 4-methylphenol with a chlorinating agent in the presence of a catalyst system of one or more Lewis acids in a total amount of 0.1-10% by weight and one or more diaryl sulphides in a total amount of 0.1-10% by weight, all based on the amount of 4-methylphenol. The reaction temperature is 0.degree.-100.degree. C. The chlorinating agent is used in an amount of 0.5-1.5 mol per mole of 4-methylphenol. The reaction can be carried out until virtually complete consumption of the 4-methylphenol, high isomeric selectivity and high stage selectivity being observed.

Process for the preparation of 2-chloro-4-methylphenol

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Leverkusen, Germany

Helmut Fiege