Basf Aktiengesellschaft

Guido Kuth

Erwin Hahn

Paul Guenthert

Burkhard Ort

Christoph Bomba

A process for preparing a compound of the formula I ##STR1## where R.sup.1 to R.sup.4 are each, independently of one another, hydrogen, alkyl, alkoxy, hydroxyl or halogen, comprises reacting a compound of the formula II ##STR2## with a compound of the formula III ##STR3## in the presence of sulfur or a sulfur donor at elevated temperature. The compounds prepared according to the invention are suitable, for example, as diazo components.

Preparation of 2-(4-aminophenyl)benzothiazole compounds

A process for the preparation of a quinophthalone of the formula ##STR1## in which X is hydrogen, chlorine or bromine and n is an integer from 1 to 4, by condensing 8-aminoquinaldine with a phthalic anhydride, optionally monosubstituted or polysubstituted by chlorine or bromine, in the presence of molten benzoic acid acting as diluent.

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Ludwigshafen, Germany

Guido Kuth