Ciba-geigy Corporation

Ciba-geigy Ag

Ciba-geigy Corporatioin

Paul Rys

Martin Clausen

Rolf Vogelsanger

Walter Marte

Junkuan Wang

Hans R Gruniger

Wang Junkuan

Rudolf Kern

Process for the preparation of compounds of the formula HO-Ar-COOH in which Ar is a substituted or unsubstituted aromatic ring system, by oxidizing, by means of oxygen or compounds which donate oxygen, compounds of the formula HO-Ar-R.sub.1 in which R.sub.1 is alkyl having 1 to 5 carbon atoms and Ar is as defined above, or the O-acyl derivatives of these compounds, in an organic solvent at 80.degree. to 130.degree. C. and in the presence of an acylating agent, a cobalt and/or manganese compound and a compound which donates bromide, ions, and subsequently hydrolysing the products in a conventional manner. In the presence of the acylating agent, a selective oxidation of the hydroxyl-substituted aromatic compounds to carboxylated hydroxy compounds, which are obtained in a good state of purity and yield, is obtained without the application of pressure. The compounds obtained in accordance with the process are, for example, valuable intermediates for the preparation of dyes, plastics and pharmaceuticals.

Process for the preparation of carboxylated aromatic hydroxy compounds

Process for dyeing and printing cellulosic fiber materials with vat dyes in the presence of enediols as reducing agents and alkali, using in addition small amount of organic water-miscible solvents, for example low molecular weight alcohols, when reducing the vat dyes. The vatting of the vat dyes proceeds uniformly and completely within a relatively short time, and the resulting vat dyes are reproducible and notable for high levelness and fastness properties.

Dyeing and printing of cellulosic fibre materials with vat dyes with

Process for the preparation of alkyl-substituted phenols or naphthols by oxidizing the corresponding dialkylbenzenes or dialkylnaphthalenes, respectively, at elevated temperatures of, for example, 70.degree. to 130.degree. C. by means of oxygen or oxygen donors, in the absence of solvents and in the presence of an alkali metal salt or alkaline earth metal salt of an organic carboxylic acid having 5 to 14 carbon atoms, to give the corresponding 2,6-dialkylnaphthalene-or 1,4-dialkylphenyl monohydroperoxides and subsequently hydrolysing the latter in a customary manner. The process results in pure, easily isolatable products in a good yield. The products of the process according to the invention are valuable precursors and intermediates for, inter alia, dyes, plastics or pharmaceuticals.

Process for the preparation of alkyl-substituted phenols or naphthols

Process for the preparation of 2,6-dihydroxynaphthalene from 2,6-dialkylnaphthalenes, which are dissolved in an inert solvent and are oxidized at temperatures from 50.degree. to 150.degree. C. by means of oxygen or oxygen donors, in the presence of an alkali metal salt or alkaline earth metal salt of an organic carboxylic acid having 5 to 14 carbon atoms, to give the corresponding 2,6-dialkylnaphthalene dihydroperoxides, and the latter are subsequently hydrolysed. The process results in pure, easily isolatable products in a good yield. The process products according to the invention are valuable intermediates for, inter alia, dyes, plastics, synthetic fibres, polymeric liquid crystals or pharmaceuticals.

Process for the preparation of 2,6-dihydroxynaphthalene

A novel process for the electrolytic deposition of silicon from a melt containing covalent silicon compounds, in particular silicon tetrahalides, and furthermore aluminum halides, alkali metal halides and halides of transition metals is carried out at relatively low temperatures of 100.degree. to 350.degree. C. in an inert temperature. The silicon is deposited cathodically or anodically onto electrically conductive material. The silicon coatings are homogeneous and adhere firmly to the substrate. The coated materials can be used for the production of photoconductive or photovoltaic devices.

Process for the production of polycrystalline silicon coatings by

Compounds which contain a group bonded directly to an aromatic nucleus of the formula

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Zurich, Switzerland

Paul Rys