Ciba-geigy Corporation

Claude Gremmelmaier

Jean Riethmann

Beat M Aebli

Indolines of the formula ##STR1## wherein R.sub.1 is hydrogen or C.sub.1 -C.sub.4 alkyl and each of R.sub.2 and R.sub.3 independently of the other is hydrogen, C.sub.1 -C.sub.4 alkyl or phenyl, are prepared by cyclodehydrating a 2-(2'-aminophenyl)ethanol of formula ##STR2## wherein R.sub.1, R.sub.2 and R.sub.3 are as defined above, at 150.degree.-350.degree. C. in the presence of an amorphous aluminum silicate. The indolines of the above formula are useful intermediates for the synthesis of plant protective agents.

Process for the preparation of indolines

A process for the production of cyameluric chloride is disclosed which comprises passing cyanuric chloride, mixtures of cyanuric chloride and cyanogen chloride, or cyanogen chloride, at temperatures of 200.degree. to 700.degree. C., together with oxygen over active charcoal, and separating the resulting cyameluric chloride by desublimation from the gas mixture obtained. Cyameluric chloride is a valuable intermediate.

Process for producing cyameluric chloride

A process for producing alkoxy ketones of formula I ##STR1## wherein R.sub.1 represents an alkyl group having 1 to 8 carbon atoms, R.sub.2 represents hydrogen or an alkyl group having 1 to 4 carbon atoms, and n represents 1 or 2, by dehydrogenation of a corresponding alkoxyalkanol on a copper-containing catalyst which has been activated by treatment with hydrogen at 120.degree. to 450.degree. C., in which process the activated catalyst is firstly brought into contact at 230.degree. to 350.degree. C. with the vapor of the alkoxyalkanol to be dehydrogenated; hydrogen is subsequently passed over the catalyst at 250.degree. to 450.degree. C.; and then the dehydrogenation is performed at 150.degree. to 450.degree. C. on the catalyst pretreated in this manner, is disclosed.

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Aesch, Switzerland

Claude Gremmelmaier