Rutgerswerke Aktiengesellschaft

Degussa Aktiengesellschaft

Ruetgerswerke Aktiengesellschaft

Winfried Orth

Werner Fickert

Wolfgang Weiss

Hans W Kleffner

Emmerich Pastorek

Manfred Maurer

Fritz W Lange

Jurgen Engel

Peter Emig

Gerhard Scheffler

Gunter E Jeromin

Hans Pohle

Albrecht Laufer

Stefan Sendelbach

Heinrich Miele

Bernd Rapp

Dietrich Tonnius

Josef Gotz

Michael Hassler

Rolf Losch

A process for the preparation of isomer-free 2,5-dichloropyridine comprising alkoxylating 2-chloro-pyridine or 2-bromo-pyridine in the presence of a base at elevated temperatures, chlorinating with gaseous chlorine the alkoxylated product at ambient temperatures in an aqueous suspension in the presence of an auxiliary base, a small amount of a catalyst and optionally a small amount of an emulsifier, treating the isomer reaction mixture with a Vielsmeyer-Haack reagent, subjecting 2,5- and 2,3-dichloropyridine mixture to water vapor distillation and crystallizing the crystalline product from an alcohol-water mixture.

Preparation of isomer-free 2,5-dichloro-pyridine

In the production of 9,9-bis-(4-hydroxphenyl)-fluorene by condensation by fluorenone and phenol in a molar ratio of 1:4 to 1:8 at 30.degree. to 90.degree. C. in the presence of gaseous hydrogen chloride and .beta.-mercapto-propionic acid as catalyst, the improvement comprising mixing the completed reaction mixture with a polyalkylene glycol, distilling excess phenol from the mixture, and mixing the distillation residue with a solvent miscible with the polyalkylene glycol, recovering the crystallized product, suspending the crystallized product in water and heating the suspension to obtain highly pure 9,9-bis-(4-hydroxyphenyl)-fluorene as white crystals.

Preparation of 9,9-bis-(4-hydroxyphenyl)-fluorene

In a process for the preparation of 9,9-bis-(4-hydroxyphenyl)-fluorene by condensing fluorenone and phenol in a molar ratio of 1:4 to 1:8 at 30.degree. to 90.degree. C. in the presence of gaseous hydrogen chloride and .beta.-mercapto-propionic acid catalyst, the improvement comprising distilling water of reaction and dissolved hydrochloric acid from the completed reaction mixture, dissolving the distillation residue in a nitrile, separating the crystallized adduct of nitrile and 9,9-bis-(4-hydroxphenyl)- fluorene from the nitrile and optionally dissociating the adduct to recover high purity 9,9-bis-(4-hydroxphenyl)- fluorene.

A method for the production of heavy metal-free pyridine -3-sulfonic acid by oxidation of 3-chloro-pyridine to 3-chloro-pyridine-N-oxide, substitution of the chlorine through a sulfonic acid group, and subsequent reduction to pyridine-3-sulfonic acid. The method can be carried out using raw 3-chloropyridine-N-oxide and direct further reaction of the pyridine-3-sulfonic acid-N-oxide in the presence of Raney nickel in an alkaline solution.

Production of pyridine-3-sulfonic acid

A process for the recovery of isomeric pure 7-chloro-quinaldine from isomeric mixtures of chloro-quinaldines comprising dissolving the isomeric mixture of chloro-quinaldines in an organic solvent, adding an aqueous tartaric acid solution to the organic solution to form the tartrate of 7-chloro-quinaldine in crystalline form, recovering the crystals and treating the same with a base to obtain 7-chloro-quinaldine.

Novel separation process

A process for the production of 2-hydroxypyridine from 2-chloro-pyridine which is reacted with an aqueous alkaline solution in the presence of a tertiary alcohol.

Process for the production of 2-hydroxypyridine

A process for the preparation of quinuclidine-3-methanol comprising reacting quinuclidine-3-one acid addition salt with an alkali metal cyanide in an aqueous media to obtain 3-cyano-3-hydroxy-quinuclidine, reacting the latter with anhydrous methanol in the presence of hydrogen chloride gas followed by treatment with aqueous alkali to obtain methyl 3-hydroxy-quinuclidine-3-carboxylate, reacting the latter with thionyl chloride to form methyl 1-azabicyclo(2,2,2)oct-2-ene-3-carboxylate, hydrogenating the latter with Raney nickel to obtain methyl 1-azabicyclo(2,2,2)octane-3-carboxylate and reducing the latter to obtain quinuclidine-3-methanol which is an intermediate for mequitazine which is useful as an antihistaminic.

Preparation of quinuclidine-3-methanol

Hair dye compositions based on oxidation hair dyes which contain developer components, coupling components and oxidation components, characterized in that they contain one or more aminopyrrole derivatives of the formula: ##STR1##

Hair dye composition

There is described a process for the production of 2-amino-3-nitro-6-(4-fluorobenzylamino)-pyridine which consists essentially of reacting 2-amino-3-nitro-6-methoxypyridine with 4-fluorobenzylamine in water at elevated temperature; in a given case the nitro group can be subsequently reduced and a carbethoxy group introduced.

Process for the production of

A novel method of chlorinating the alkyl side chains of a nitrogen containing heterocyclic comprising reacting an alkyl substituted heterocycle with trichloroisocyanuric acid at temperatures of 20.degree. to 200.degree. C. to obtain the same in high yields.

Side chain chlorination process of heterocycles

In a process for the preparation of 2,5-diloweralkyl-1,4; 3,6-dianhydrosorbitols by reacting 1,4;3,6-dianhydrosorbitol with an alkylating agent in an alkaline aqueous-organic solvent solution, the improvement comprising using a tertiary alkanol as the organic solvent.

Preparation of 2,5-diloweralkyl-1.4:3,6-dianhydrosorbitols

A method for the preparation of 4-halogenonaphthalic acid anhydrides by halogenation of an aqueous solution of an alkali salt of the naphthalic acid with halogen or alkali metal hypohalogenite wherein a solution of the alkali metal salt of the naphthalic acid is treated with a water soluble magnesium salt and at least an equal molar amount of an alkakli metal hydroxide, halogenating this reaction mixture at a temperature in the range of 10.degree. to 25.degree. C. and subsequently acidifying the reaction mixture. In a second embodiment of the invention, an aqueous solution of alkali metal carbonate is used in place of the magnesium salt and alkali metal hydroxide.

Method for preparation of 4-halogenonaphthalic acid anhydrides

New 2-aminonitropyridine derivatives are disclosed of the formula: ##STR1## wherein the nitro group is in the 3- or 5-position and X represents hydrogen, an alkoxy group with 1 to 3 C atoms or an unsubstituted or alkyl- or hydroxyalkyl substituted amino group, the alkyl portion of which has 1 to 3 C atoms

Pyrrole containing 2-aminonitropyridine derivatives

An improved process for the preparation of fluorene-9-carboxylic acid comprising reacting fluorene and a dialkyl carbonate with alkyls of 1 to 5 carbon atoms in the presence of a member of the group consisting of alkali metal hydrides or potassium alcoholate of an aliphatic alcohol of 1 to 5 carbon atoms, neutralizing the mixture and saponifying the resulting fluorene-9-carboxylic acid ester to obtain fluorene-9-carboxylic acid in good yields.

Process for the preparation of fluorene-9-carboxylic acid

A novel process for the preparation of quinolinic acid comprising reacting quinoline in an aqueous acid with hydrogen peroxide in the presence of at least one cation selected from the group consisting of vanadyl V, cobalt III, titanyl IV and osmium VIII cations at 50.degree. to 100.degree. C. and then oxidizing with chlorite or chlorate ions to form quinolinic acid.

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Hassloch, Germany

Winfried Orth