Dynamit Nobel Aktiengesellschaft

Klaus Schrage

Hermann Richtzenhain

Egon N Petersen

Klaus Ruff

Helmut Aus Der Funten

Bernhard Falk

Disclosed is a process for the cleavage of chlorosiloxanes in the gas phase at temperatures between 350 and 1450.degree. C. to form chlorosilanes and silicon dioxide as reaction products. The claimed process is preferably performed in the presence of metallic silicon or ferrosilicon. The procedure can be combined with the large-scale technical production of chlorosilanes by the chlorination or hydrochlorination of silicon. The inventive process makes it possible to perform the chlorination or hydrochlorination of silicon with the formation of chlorosilanes in an increased yield while reducing the formation of by-products.

Process for the cleavage of chlorosiloxanes

A process for preparing an alkali salt of d,l-phenylalanine and the free acid thereof is disclosed. According to the invention an alkali salt of phenylpyruvic acid is reacted at elevated pressure with hydrogen and ammonia in the presence of a noble metal catalyst of Group VIII. If the acid is desired it is obtained by acidification of the corresponding salt.

Method of preparing d,l-phenylalanine

Process for the side-chain chlorination of aromatic compounds completely halogenated in the nucleus, containing methyl groups, and having the general formulas: ##STR1## wherein y=1 or 2, z=0 to 1, x=6-(y+z), n=0 to 8 and k=(8-n) and the methyl groups are, respectively, in the ortho, meta or para position to one another and in the p-position to the oxygen bridge, by thermal chlorination in the liquid phase. The bis-monochloromethyl compounds of formula (II) are novel compounds. The chlorination products are useful as intermediates.

Process for the side-chain chlorination of perhalogenated methyl

Ar-octahalogendiphenylether-4,4-dimethanols

Brominated dibenzofuran of the formula ##STR1## WHEREIN X + Y = 6.0 TO 7.0 AND Y = 0 TO 0.3. The brominated dibenzofuran can be prepared by reaction of bromine and dibenzofuran at 0.degree. and 150.degree. C in the presence of halogenation catalyst. The products are useful as flameproofing agents for organic polymers, e.g. polyethylene.

Heptabromodibenzofuran, highly brominated dibenzofurans and the

A method is provided for the preparation of 2-arylbenzoxazoles and 2-arylbenzthiazoles which comprises reacting a trichloromethyl-substituted aromatic compound with an aromatic compound carrying one amino group and one hydroxy or mercapto group in ortho position to each other. The compounds obtained by the process of the invention form the basis of numerous optical brighteners and find use in dyes, cosmetics, pharmaceuticals and heat-resistant fibers.

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Konigswinter-Uthweiler, Germany

Klaus Schrage