Organic compounds in which the bromine is covalently bonded to carbon, nitrogen and oxygen, are a very important group of organic halogen compounds. Even naturally occurring bromine containing organic compounds produced by marine and terrestrial plants, bacteria, fungi, insects, marine animals, and some higher animals, number nearly 1500 compounds. (A) Historically, the organic bromine compound, Tyrian, or Royal Purple, (dibromoindigo) extracted from a Mediterranean Sea mollusk, was one of the first used dyes. (B) Organic bromine compounds in which the bromine atom is retained in the final molecular structure, and where its presence contributes to the properties of the desired products. E.g. flame retardants, biocides, gasoline additives, halons, bromobutyl rubber, pharmaceuticals, agrochemicals, dyes, methyl bromide, ethylene dibromide, and halons. Organic bromine compounds have traditionally played an important role as intermediates in the production of agrochemicals, pharmaceuticals and dyes, while new process developments that result in new applications in ultraviolet (uv) sunscreens, high performance polymers, and others, are forecast to increase their market share. The world consumption of bromine for intermediates is dwarfed by the corresponding consumption of chlorine. On the simple grounds of raw material halogen cost, organic chlorine intermediates have dominated in the manufacture of low value, high volume commodity products. Bromine, however, has tended to the nucleophilic substitution in the aliphatic series may be accompanied by elimination, and the yield of the target compound depends on a number of factors (structure of the initial compound, presence and nature of solvent and catalyst, etc). 1-2 thus, alkyl bromides compete more favorably with chlorine for application as an intermediate in the above mentioned, more specialized, higher value areas. The diverse applications of organic bromine intermediates in commercial manufacture provide ample illustrations of the many virtues of bromine chemistry serving to outweigh the penalty of high halogen cost. (a) Improved selectivity in the production of bromine intermediates. (b) Improved reactivity of the intermediates in bromine displacement. (c) Cleaner processes reduction of waste, and reduced environmental impact. While (a) and (b) provide obvious improvements in manufacturing economics, the rapidly increasing demand for environmentally clean chemical processes makes (c) a major, and often dominant factor, in the choice of the intermediate and process route for a new production.
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