Basf Aktiengesellschaft

Basf Aktiengeschaft

Manfred Gaeng

Reinhold Kohlhaupt

Walter Bieg

Lothar Haas

Matthias Fankhaenel

Guenter Engelhardt

Gerhard Hamprecht

Manfred Patsch

Karl-Heinz Koenig

Gerd Husslein

Peter Miederer

Peter Schultz

Alfred Hackenberger

Wolfgang Hoffmann

Heinz Saukel

Walter Boehm

Josef Koenig

Leucoindigo preparatations in granule form

A process for preparing 2-methylbenzoxazole by cyclizing acetamidophenol with the simultaneous elimination of the water of reaction. The process involves the drying and melting of the acetamidophenol, the cyclization of acetamidophenol to 2-methylbenzoxazole, and the removal of the water of reaction and the 2-methylbenzoxazole from the reaction mixture after the cyclization step by distillation. All the steps are carried out in a dryer.

Preparation of 2-methylbenzoxazole

A process for the preparation of purified indigo comprises extracting the aqueous alkaline indoxylate solution arising from the synthesis with an inert water-insoluble solvent in the absence of oxygen before oxidizing the indoxylate solution to give indigo.

Purification of indigo

A process for the preparation of 2,4-dichloro- or 2-methyl-4-chlorophenoxyacetic acid or .alpha.-2,4-dichloro- or .alpha.-2-methyl-4-chlorophenoxypropionic acid by reacting phenoxyacetic or 2-methylphenoxyacetic acid or .alpha.-phenoxypropionic or .alpha.-2-methylphenoxypropionic acid with chlorine in water, wherein phenoxyacetic acid or phenoxypropionic acid is precipitated from an aqueous solution thereof, chlorine gas is passed into the resulting suspension of phenoxyacetic or 2-methylphenoxyacetic acid or .alpha.-phenoxypropionic or .alpha.-2-methylphenoxypropionic acid in water at from 30.degree. to 70.degree. C. at a rate not exceeding the rate at which it is consumed in the suspension, until from 100 to 110% of the theoretically required amount of chlorine gas has been taken up by the suspension, and the 2,4-dichloro- or 2-methyl-4-chloro-phenoxyacetic acid or .alpha.-2,4-dichloro- or .alpha.-2-methyl-4-chloro-phenoxypropionic acid is isolated from the suspension.

Preparation of chlorinated phenoxyalkanoic acids

Methyl m-nitrobenzoate is prepared by a process in which an isomer mixture is treated with from 10 to 1000% by weight of water in the presence of from 0.05 to 20% by weight of an emulsifier, the percentages being based on the weight of the isomer mixture,

Preparation of methyl m-nitrobenzoate

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Bobenheim-Roxheim, Germany

Manfred Gaeng