Hoechst Aktiengesellschaft

Rudiger Berthold

Werner H Muller

Theodor Papenfuhs

Wolfgang Tronich

Bernhard Mees

Hartmut Heise

Lothar Schmitt

In the process for the continuous preparation of aminoaryl or aminoalkyl .beta.-sulfatoethyl sulfones by reaction of the corresponding .beta.-hydroxyethyl sulfones with sulfuric acid in a molar ratio of 1:1 to 1:1.15 at temperatures above 120 .degree. C. a mixture of a .beta.-hydroxyethyl sulfone with sulfuric acid is supplied to a fluidized bed of end product produced by recycling and mechanical stirring. The mixture is reacted at 100.degree. to 200.degree. C.

Process for the continuous preparation of aminoaryl or aminoalkyl

The invention relates to a process for the preparation of aryldiazosulfonates by reacting aqueous solutions of aryldiazonium salts with solutions or suspensions of sulfites, in particular in a manner such that the presence of an excess of one of the two reactants during the reaction is substantially excluded. The process according to the invention makes it possible substantially to increase the yields of aryldiazosulfonates.

Process for the preparation of aryldiazosulfonates

The invention relates to a process for the preparation of arylhydrazine-N-sulfonic acids by reduction of aryldiazosulfonates with hydrogen in the presence of transition metal catalysts.

Process for the preparation of arylhydrazine-N-sulfonic acids

2-Amino-5-nitrotoluene is obtained in high yield by reacting 2-chloro-5-nitrotoluene with excess aqueous ammonia which has a concentration of at least 30% by weight. The product is used as a diazo component for preparing azo compounds.

Process for preparing 2-amino-5-nitrotoluene

Preparation of 3,5-dimethylaniline from 3,5-dimethyl-2-cyclohexenone azine by heating in inert solvents in the presence of a catalyst containing a noble metal of the 8th auxiliary group of the Periodic Table of Elements gives high yields when the solvent is an aliphatic ether, especially a lower dialkyl ether of a polyethyleneglycol.

Process for the preparation of 3,5-dimethylaniline

The invention provides a process for the preparation of 3,5-dimethylaniline by catalytically dehydrogenating 3,5-dimethyl-cyclohexenone oxime in the gaseous phase. The catalyst contains at least one noble metal of the 8th subgroup of the Periodic Table.

Process for the preparation of 3,5-dimethylaniline (sym. m-xylidine)

Aromatic amines are obtained from the corresponding cycloaliphatic oximes by heating the oxime to a temperature of from 150.degree. to 350.degree. C. in an ether group containing solvent in the presence of a catalyst containing a noble metal of the 8th auxiliary group of the Periodic Table of Elements. The solvent is preferably an aliphatic ether, especially a lower dialkyl ether of a polyethyleneglycol.

Process for the preparation of aromatic amines

Cyclohexanones and -hexenones ##STR1## R.sup.1 is hydrogen or

Cyclohexanones and cyclohexenones

Aromatic amines are obtained in high yield and purity by treating the corresponding cyclohex-2-en-1-on-oxime hydrochlorides with the at least threefold molar amount of acetic anhydride.

Process for the manufacture of aromatic amines from .alpha.,

The known condensation reaction of lower alkanoylacetic acid lower alkyl esters with aldehydes catalyzed by amines proceeds safe and in high yields if the amineis an aliphatic tertiary amine. The products are precursors of aromatic amines.

Process for the preparation of condensation products of acetoacetic

The N-acetoacetylamino compounds of 2,5-dimethoxy-4-chloro-aniline, 2,4-dimethyl-aniline and 2-methyl-5-chloroaniline are obtained in a good yield and excellent purity, if the above-mentioned anilines are reacted with diketene in an inert organic solvent or diluent in the presence of from 0.1 to 6%, calculated on the weight of the aniline, of water, while adding catalytic amounts of acid. An industrial aniline quality is preferably dried by heating it with a solvent forming with water an azeotropic mixture, and thereafter the amount of water required is added. The products may be used without purification as coupling components for the preparation of pigments.

Process for the manufacture of acetoacetyl-aminobenzenes

.alpha.,.beta.-Unsaturated cycloaliphatic ketoximes and their salts are obtained in high purity and yield by reacting an .alpha.,.beta.-unsaturated cycloaliphatic ketone with hydroxylamine hydrochloride, sulfate or hydrogen sulfate in water in a pH range of 0 to 4.5. The products are intermediates for aromatic amines.

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Bad Soden am Taunus, Germany

Rudiger Berthold