Selective catalytic oxybromination of hydroxyaromatic compounds

Details Selective catalytic oxybromination of hydroxyaromatic compounds Selective catalytic oxybromination of hydroxyaromatic compounds

2006-04-04

2006-04-04

Shippen, Michael L. (Department: 1621)

Organic compounds -- part of the class 532-570 series

Organic compounds

Oxygen containing

Reexamination Certificate

active

07022886

ABSTRACT:
A method for selectively brominating hydroxyaromatic compounds is disclosed. Hydroxyaromatic compounds are contacted with oxygen and a bromine source, in an acidic medium, in the presence of a catalyst selected from the group of compounds and mixtures of compounds of Group IV–VIII transition metals of the Periodic Table of Elements. The selectivity of mono-brominated products produced, predominantly in the para-position, from the method using transition metal compounds as catalysts is significantly higher than that of known methods using other catalysts. Thus, there is a significant reduction in the production of undesirable dibrominated and more highly brominated by-products.

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Search Report dated Dec. 28, 2004.

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