Bromine Compounds Limited

Joshua Hermolin

Michael Zviely

Jakob Oren

Hugo Keselman

Aaron R McMurray

David Feldman

Jacob Oren

Arieh Kampf

Amiram Groweiss

Hugo Kesselman

Dov Zamir

Compounds of the formula: ##STR1## wherein: n=0 or 1;

Amino phenoxy compounds and process for their preparation

Diaminodiphenyl-compounds of the structure selected from: ##STR1## wherein R.sub.1 and R.sub.2 can be: H, --CH.sub.3, --C.sub.2 H.sub.5, --C.sub.3 H.sub.7, --C.sub.4 H.sub.9 or ##STR2## Y can be: C(CH.sub.3).sub.2, ##STR3## n=0; 1. are purified by distilling the crude product obtained under vacuum in one step, in the presence of one or more alkaline bases.

Process for the purification of diaminodiphenyl compounds

In a process for the preparation of 4,4'-dihydroxybiphenyl of high purity 4,4'-dibromobiphenyl is hydrolized in the presence of a copper compound catalyst, the insoluble materials comprising the catalyst is filtered off from the product mixture, 4,4'-dihydroxybiphenyl is precipitated by adjusting the pH and crude 4,4'-dihydroxybiphenyl separated from the product mixture is fractionally distilled to obtain substantially pure 4,4'-dihydroxybiphenyl.

Process for the preparation of pure 4,4'-dihydroxybiphenyl

In a process for the preparation of mixtures of 2,3-dimethylphenol and 3,4-dimethylphenol a mixture of 2,3-dimethyl-bromobenzene and 3,4-dimethyl-bromobenzene is hydrolized in an aqueous alkaline solution in the presence of a copper compound catalyst of the formula:

Process for the preparation of 2,3-dimethylphenol and of

In a process for the preparation of 3-phenoxybenzylalcohol, 3-phenoxytoluene is reacted with dibromodimethylhydantoin in a non-polar solvent, followed by hydrolysis of the products of the first reaction step. The process provides highly pure 3-phenoxybenzylalcohol with high yields.

Process for the preparation of 3-phenoxybenzylalcohol

A process is disclosed for the preparation of 2,2-dibromonitrilopropionamide, in which cyanoacetamide is brominated in aqueous medium with bromine or hydrobromic acid, in the presence of an oxidizing agent and at elevated temperature, followed by cooling of the reaction mixture to precipitate the DBNPA.

Process for the preparation of 2,2-dibromonitrilopropionamide

1,2,5,6,9,10-Hexabromocyclododecane (HBCD) is prepared in an anhydrous process in polar solvents, by the bromination of 1,5,9-cis, trans, trans-cyclododecatriene at relatively high temperatures.

Process for the preparation of 1,2,5,6,9,10-hexabromocyclododecane

The present invention relates to a process for the manufacture of mixtures of 3-phenoxybenzyl bromide and 3-pnenoxybenzal bromide using dibromodimethylhydantoin as brominating agent. According to the process, the reaction between the m-phenoxytoluene and the brominating agent is carried out in a non-polar solvent at temperatures above 65 degrees C. The molar ratio between the reactants is selected in the range of between 0.5:1 to 1.25:1 of the brominating agent towards the 3-phenoxytoluene. In a preferred embodiment, a radical initiator is incorporated being selected from the group consisting of ultraviolet rays and compounds containing azo-groups, peroxides or mixtures thereof. According to a most preferred embodiment the addition of the free radical and of the brominating agent is carried out gradually. The process is characterized by its very high yield, the products obtained being of a very high quality.

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Ramat Hasharon, Israel

Joshua Hermolin