Bayer Aktiengesellschaft

Harro Schlesmann

Chiraranjan Podder

Adolf Sicheneder

Wilfried Nolte

Thomas Kleiner

Klaus Reinartz

Stefan Dietl

The preparation of N-cyclohexylthiophthalimide from cyclohexylsulphenyl chloride and phthalimide can be reproduced more reliably if the cyclohexylsulphenyl chloride is prepared in sire by chlorinating dicyclohexyl disulphide.

Process for preparing N-cyclohexylthiophthalimide

Bis-benzthiazolyl alkyl sulfenimides are produced by a process in which alkyl amines are reacted with optionally substituted 2-mercaptobenzthiazoles in the presence of oxygen or oxygen-containing gases and copper and/or copper compounds and in the presence of inert organic solvents.

Process for the production of bis-benzthiazolyl alkyl sulfenimides

Crude 2-mercaptobenzothiazole is purified by a process in which the crude 2-mercaptobenzothiazole is dissolved in relatively high-boiling aliphatic or cycloaliphatic alcohols or in mixtures of the alcohols mentioned or azeotropes thereof with water at temperatures of 60.degree. to 200.degree. C., optionally under elevated pressure, or is suspended in relatively high-boiling aliphatic or cycloaliphatic alcohols, aliphatic or cycloaliphatic ethers, organic acids or esters thereof at temperatures of 10.degree. to 100.degree. C., the solution or suspension is subsequently cooled and the product precipitating is filtered off and optionally washed.

Process for the purification of crude 2-mercaptobenzothiazole

4-nitrodiphenylamines may be produced by an improved process from 4-halo nitrobenzenes and primary aromatic amines in the presence of potassium carbonate and copper compounds, wherein

Process for the production of 4-nitrodiphenylamines

The reaction of 4-nitrohalogenbenzenes with primary aromatic amines in the presence of potassium carbonate and copper compounds to 4-nitrodiphenylamines gives better yield of purer products when synthetic polyamides are added.

The reaction of 4-nitrohalobenzenes with primary aromatic amines in the presence of potassium carbonate and copper compounds to produce 4-nitrodiphenylamine results in products with improved purity and yield if (1) carbonic acid amides or their derivatives are added, (2) 3 to 5 mol of amine are used per mole of halonitrobenzene and (3) 1.2 to 2 mol of the amine are added before the beginning of the reaction and the remainder during the reaction at such a rate that the molar excessive amine over halonitrobenzene is always from 100 to 400%.

Process for the preparation of 4-nitrodiphenylamines

An improved process for the preparation of 4-nitrodiphenylamines by the reaction of 4-nitrohalobenzenes with primary aromatic amines in the presence of potassium carbonate and copper compounds is characterized in that sulpholane dimethylsulphone, dimethylacetamide, diethylacetamide, tetramethylurea, tetraethylurea or mixtures thereof are used as solvents and 3 to 5 mol of amine are used per mol of halogenated nitrobenzene, from 1.2 to 2 mol of said amine being added before the beginning of the reaction and the remainder during the reaction at such a rate that the molar excess of unreacted amine over unreacted halogenated nitrobenzene is constantly at least 100%.

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Odenthal, Germany

Harro Schlesmann