Basf Aktiengesellschaft

Helmut Karn

Toni Dockner

Uwe Kempe

Anton Frank

Hermann Koehler

Matthias Wetzler

Klaus Ebel

Reinhold J Leyrer

Thomas Loerzer

Christof Taubitz

Thomas Bluemel

A process for the preparation of imidazoles which are substituted with p-nitrophenyl in the 2- and/or 4- and/or 5-position and may carry additional substituents, by reacting imidazoles which are substituted by phenyl in the 2- and/or 4- and/or 5-position and may carry additional substituents with mixtures of sulfuric acid and nitric acid, wherein the reaction is carried out in the presence of urea.

Preparation of p-nitrophenyl-imidazoles

Hexaarylbisimidazoles I ##STR1## where Ar.sup.1, Ar.sup.2 and Ar.sup.3 are each aryl, of which Ar.sup.2 and Ar.sup.3 can be linked to form an anellated ring system, are prepared by oxidizing the corresponding triarylimidazoles II in an aqueous/organic two-phase system in the presence of active amounts of an onium salt III.

Preparation of hexaarylbisimidazoles

Process for the preparation of 1-alkylimidazoles of the general formula (I) ##STR1## where R.sup.1 is alkyl, R.sup.2 and R.sup.3 are hydrogen, alkyl, aryl, arylalkyl, or alkylaryl, R.sup.4 is carboxy, alkoxycarbonyl R.sup.5 OCC--, carbamoyl, or cyano, and R.sup.5 is an alkyl of from 1 to 8 carbon atoms--by the reaction of imidazoles of the general formula (II) ##STR2## with dialkyl sulfates of the general formula (III)

Preparation of 1-alkylimidazoles

A process for the manufacture of 5-hydroxymethylimidazoles by reaction of an imidazole with formaldehyde or an oligomer of formaldehyde in aqueous hydrochloric acid solution containing from 5 to 18% by weight of hydrogen chloride, at from 80.degree. to 160.degree. C., if desired in a closed system under pressure, followed by isolation in the form of its hydrochloride of the 5-hydroxymethylimidazole obtained.

Preparation of 5-hydroxymethylimidazoles

1-Hydroxymethylimidazoles which are unsubstituted or alkyl-substituted in the 2-position, their manufacture and their use as chemical intermediates, e.g. for other imidazole derivatives or for the drug cimetidine.

Process for preparing 4-methyl-5[(2-aminoethyl)thiomethyl)]-imidazole

Process for producing 1-hydroxymethylimidazoles

1-Alkyl-5-nitroimidazoles are prepared by reacting a 5-nitroimidazole with an alkylating agent in the presence of an aliphatic carboxylic acid. The products are intermediates for the production of dyes, textiles auxiliaries and insecticides.

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Ludwigshafen, Germany

Helmut Karn