Dynamit Nobel Aktiengesellschaft

Huels Aktiengesellschaft

Gunter Zoche

Hermann Richtzenhain

Wilhelm Vogt

Hans-Werner Engels

Paul Spielau

Marcel Feld

Paul Riegger

Karl H Neuschaeffer

Roshdy Ismail

Karl-Heinz Neuschaffer

Hans-Jurgen Gebert

Robert W Laube

Ketoximosilanes are prepared by reacting alkyl- or alkenyl-acetoxysilanes with ketoximes in the presence of ammonia. The ketoximosilane reaction products are useful as cross-linking agents for organopolysiloxane compositions.

Process for the manufacture of ketoximosilanes

Disclosed is a process for the production of ketoximosilanes and ketoximoalkoxysilanes. Ketoximes are reacted with alkyl trialkoxysilanes in the presence of a catalyst. The reaction is catalyzed by basic compounds which are dissolved or suspended in the ketoxime. The basic compounds that are used are alkali metals and, preferably, the oxides, hydroxides and carbonates of the elements from the 1st and 2nd group and the 3rd sub-group of the Periodic Table of Elements and lanthanides. The process according to the invention prevents the decomposition and explosion that easily occur in the known processes. The ketoximosilanes prepared according to the invention are valuable crosslinking agents for organopolysiloxane compositions.

Process for the preparation of ketoximosilanes

The present invention relates to a method of preparing 10,11-dihydro-5H-dibenzo[a,d]cycloheptene-5-one or substitution products thereof from dibenzyl-o-carboxylic acid or its corresponding substitution products, by cyclocondensation. The cyclocondensation is performed in either of two ways, namely (a) with catalytic amounts of a concentrated acid as catalyst, or (b) with the aid of di- and/or trichloromethyl aromatic compounds in the presence of catalysts, preferably catalysts from the group of the Lewis acids.

Process for preparing 10,11-dihydro-5H-dibenzo[a,d]cycloheptene-5-one

Molded parts having high flexural strength, based on alkali silicates, can be produced by casting and/or press-molding and curing by heating from aqueous molding compositions which are prepared from an oxide mixture containing amorphous silicic acid and aluminum oxide, as well as, optionally, as an additional component, aqueous, amorphous, disperse-powdery silicic acid, dissolved SiO.sub.2, and alkali from alkali silicate solutions, optionally alkali hydroxide or its aqueous solutions and, if desired, fillers, by means of mixing under agitation. By addition of a blowing agent inorganic foamed products can be obtained.

Aqueous curable molding compositions based on inorganic ingredients and

A support or base for low-vibration mounting of machines or the like is made by hardening a molding material in a mold. The base contains a hardened inorganic material with a density of 2.2 to 3.0, particularly 2.5 to 2.7 g/cm.sup.3, is made from

Machine base and process for manufacture thereof

A process is provided for the recovery and recycling of spent cobalt and/or manganese catalysts used in the air oxidation of alkyl aromatics in acetic acid. The catalysts are isolated in the form of oxalates of extremely low solubility from the acetic acid mother liquors and the cobalt oxalate dihydrate and/or manganese oxalate dihydrate catalysts are restored by the joint action of hydrogen bromide and acetic anhydride, acetyl bromide, or a mixture thereof, to a form in which they are soluble in acetic acid and can be used, again, as oxidation catalysts.

Method for the recovery and reuse of cobalt and/or manganese components

In a process for preparing substituted or unsubstituted carboxylic acid chlorides of the benzene series by contacting the corresponding carboxylic acid ester with an aromatic compound containing at least one nuclearly bound trichlormethyl group in the presence of a molybdenum catalyst, the improvement which comprises introducing into the reaction mixture prior to distillation of the carboxylic acid chloride a complexing agent which complexes with the molybdenum catalyst.

Method of preparing carboxylic acid chlorides of the benzene series

A process for preparing substituted or unsubstituted carboxylic acid chlorides of the benzene series which comprises contacting the corresponding carboxylic acid ester with an aromatic compound containing at least one nuclearly bound trichloromethyl group in the presence of a molybdenum catalyst.

Process for the preparation of carboxylic acid chlorides of the benzene

Process for the preparation of .alpha., .alpha.,.alpha.,.alpha.',.alpha.'-pentachloro-o-xylene by the reaction of o-xylene with chlorine in the presence of solvent and under actinic light radiation, characterized in that the reaction is performed at temperatures above 75.degree. up to 140.degree. C with carbon tetrachloride as solvent, with the introduction of chlorine, or in some cases by means of chlorine activated in the gas phase.

Process for the preparation of

Process for the preparation of especially pure 2,2-bis-(4-hydroxy-3-chlorophenyl)-propane (dichlordiane, DCD) by the chlorination of 2,2-bis-(4-hydroxyphenyl)-propane in the presence of solvents that are substantially indifferent to chlorine by prior-art methods; then, for purification, the chlorinated bis-phenol is dissolved in halogenated hydrocarbons and/or halogenated hydrocarbon in which are liquid at 20.degree.C which they are readily soluble in the absence of an aqueous phase but in which they are at most only slightly soluble after the addition of water thereto; and the 2,2-bis-(4-hydroxy-3-chlorophenyl)-propane, is thereby precipitated from this aqueous solution.

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Bonn, Germany

Gunter Zoche