- A PROCESS FOR THE PREPARATION OF BRONOPOL
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The invention provides a process for preparing bronopol, which process comprises charging a reaction vessel with water, bromopicrin, nitromethane and paraformaldehyde, gradually feeding a base into said reaction vessel under stirring, bringing the reaction to completion and separating bronopol from the aqueous reaction mixture.
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Page/Page column 19
(2009/10/21)
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- CONTINUOUS PROCESS OF PREPARING BROMOPICRIN
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A continuous process of preparing bromopicrin is disclosed. The process is effected by transferring a continuous flow of a first mixture and a continuous flow of a second mixture into a first reactor, the first mixture containing nitromethane and bromine and the second mixture containing an aqueous solution of an alkaline substance, to thereby obtain a reaction mixture which comprises bromopicrin in said first reactor; and collecting the bromopicrin from the reaction mixture. Highly pure bromopicrin obtained by this process is also disclosed.
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Page/Page column 25-28
(2009/01/20)
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- PROCESS OF PREPARING BROMOPICRIN
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Process of preparing high purity bromopicrin, and high purity bromopicrin produced therefrom. Providing a mixture of nitromethane and bromine, and preferably water, and absent of organic solvent. Adding an aqueous solution of an alkaline substance to the mixture, thereby providing a reaction mixture containing bromopicrin, the adding performed such that no excess of the alkaline substance occurs in the reaction mixture during the adding. Collecting the organic phase (containing the bromopicrin) from the reaction mixture. No need for subjecting the organic phase of the reaction mixture to distillation or extraction, for obtaining near quantitative yield of bromopicrin having purity of at least equal to or greater than 96 weight percent. Process parameters controlling selectivity of reaction forming bromopicrin are molar ratio of bromine and nitromethane in the mixture; reaction temperature while bromopicrin is formed; concentration of the alkaline substance in the aqueous solution; and reaction time.
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Page/Page column 51-57
(2008/06/13)
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- Halonitromethane Drinking Water Disinfection Byproducts: Chemical Characterization and Mammalian Cell Cytotoxicity and Genotoxicity
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Halonitromethanes are drinking water disinfection byproducts that have recently received a high priority for health effects research from the U.S. Environmental Protection Agency (EPA). Our purpose was to identify and synthesize where necessary the mixed halonitromethanes and to determine the chronic cytotoxicity and the acute genotoxicity of these agents in mammalian cells. The halonitromethanes included bromonitromethane (BNM), dibromonitromethane (DBNM), tribromonitromethane (TBNM), bromochloronitromethane (BCNM), dibromochloronitromethane (DBCNM), bromodichloronitromethane (BDCNM), chloronitromethane (CNM), dichloronitromethane (DCNM), and trichloronitromethane (TCNM). Low- and high-resolution gas chromatography/mass spectrometry (GC/MS) was used to identify the mixed chloro-bromonitromethanes in finished drinking waters, and analytical standards that were not commercially available were synthesized (BDCNM, DBCNM, TBNM, CNM, DCNM, BCNM). The rank order of their chronic cytotoxicity (72 h exposure) to Chinese hamster ovary (CHO) cells was DBNM > DBCNM > BNM > TBNM > BDCNM > BCNM > DCNM > CNM > TCNM. The rank order to induce genomic DNA damage in CHO cells was DBNM > BDCNM > TBNM > TCNM > BNM > DBCNM > BCNM > DCNM > CNM. The brominated nitromethanes were more cytotoxic and genotoxic than their chlorinated analogues. This research demonstrated the integration of the procedures for the analytical chemistry and analytical biology when working with limited amounts of sample. The halonitromethanes are potent mammalian cell cytotoxins and genotoxins and may pose a hazard to the public health and the environment.
- Plewa, Michael J.,Wagner, Elizabeth D.,Jazwierska, Paulina,Richardson, Susan D.,Chen, Paul H.,McKague, A. Bruce
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