Bayer Aktiengesellschaft

Ciba-geigy Ag

Axel Vogel

Guido Steffan

Horst Behre

Wulf Schwerdtel

Rudolf Sundermann

Reinold Schmitz

Rolf Putter

Viktor Trescher

Friedrich Durholz

Kurt Halcour

Wolfgang Biedermann

Norbert Schenk

Guido Skipka

Karl Mannes

Wolfgang Schenk

Bernhard Albrecht

Reinhard Kaiser

Vinzenz Habermacher

Hans Frey

Lutz Kienitz

Jurgen Dammann

A process has been provided for the preparation of nitro-T-acid by nitration of naphthalene-1,3,6-trisulphonic acid from a nitration mixture which has reacted to the extent of at least 80% which naphthalene-1,3,6-trisulphonic acid or a mixture containing the latter. Nitro-T-acid (and T-acid) is an intermediate for the preparation of H-acid which, in turn, is an intermediate for the preparation of dyestuffs.

Process for the preparation of nitro-T-acid

A process for producing the magnesium salt of 3-nitro-naphthalene-1,5-disulfonic acid by sulfonating naphthalene, nitrating the sulfonation product, and separating the pure magnesium salt of 3-nitronaphthalene-1,5-disulfonic acid, which process comprises:

Process for producing the magnesium salt of

In a process for the preparation of oxalyl chloride from an oxalic acid compound of the formula ##STR1## wherein R.sup.1 and R.sup.2 are identical or different and represent hydrogen or a lower alkyl radical, and phosphorus pentachloride in the presence of phosphorus oxychloride, the improvement wherein the reaction is carried out in the presence of an amino compound of the formula ##STR2## wherein R.sup.3 represents alkyl, aralkyl, aryl or an acyl group, optionally substituted by amino or carboxamido and

Process for the preparation of oxalyl chloride

The present invention relates to a process for separating substantially pure 1,5-dinitroanthraquinone and substantially pure 1,8-dinitroanthraquinone from anthraquinone dinitration mixtures containing 1,5- and 1,8-dinitroanthraquinone, whereby such mixtures are treated with a mixture of concentrated nitric acid and an inert organic solvent, the insoluble 1,5-dinitroanthraquinone is separated off and the 1,8-dinitroanthraquinone isolated from the remaining mother liquor.

Process for separating 1,5-dinitroanthraquinone and

2-Methylpropane-1,3-diol is prepared by reacting 2-methylenepropane-1,3-diol diacetate with a monohydric, lower aliphatic alcohol in the presence of a base. Thereafter the resulting 2-methylenepropane-1,3 diol is catalytically hydrogenated to form 2-methylpropane-1,3-diol.

Process for preparing 2-methylpropane-1,3-diol

Nitroderivates of aromatic compounds which are difficult to nitrate, can readily be obtained by nitration providing that the aromatic compound is treated with nitric acid or another nitrating agent in the presence of aliphatic or cycloaliphatic hydrocarbons monosubstituted or polysubstituted by halogen, the nitro group or an alkyl sulphonyl group, and the nitro derivative formed subsequently isolated.

Process for the production of nitro derivatives of aromatic compounds

The present invention relates to a process for the purification of crude 1-nitroanthraquinone in particular to a process for separating anthraquinone and 2-nitroanthraquinone from crude 1-nitroanthraquinone by treating the crude 1-nitroanthraquinone with a mixture of concentrated nitric acid and an inert organic solvent whereby a 1-nitroanthraquinone substantially free from anthraquinone and 2-nitroanthraquinone is obtained.

Process for the purification of crude nitroanthraquinone

Dinitro-anthraquinones are produced by nitrating an anthraquinone in the presence of an indifferent organic solvent. As inert organic solvents there is suggested an aliphatic or alicyclic hydrocarbon having up to 12 carbon atoms and substituted once or several times by halogen or by the nitro group.

Process for the production of dinitro-anthraquinones

Process for the preparation of 1-nitroanthraquinone which is practically free of 1,5-dinitroanthraquinone from 1-nitroanthraquinone containing 1,5-dinitroanthraquinone, characterised in that 1-nitroanthraquinone containing 1,5-dinitroanthraquinone is treated with a mixture of concentrated nitric acid and an inert organic solvent, the undissolved constituent is separated off and the 1-nitroanthraquinone is isolated from the solution.

Process for the preparation of 1-nitro-anthraquinone which is

Preparation of very pure 1-nitroanthraquinone by heating 1-nitroanthraquinone which contains dinitroanthraquinone with the aqueous solution of a salt of sulphurous acid in the presence of an inert organic solvent.

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Cologne, Germany

Axel Vogel