Benzoic acids chlorinated

For polychlorinated biphenyls (PCBs), rate constants were highly dependent on the number of chlorine atoms, and calculated atmospheric lifetimes varied from 2 d for 3-chlorobiphenyl to 34 d for 236-25 pentachlorobiphenyl (Anderson and Hites 1996). It was estimated that loss by hydroxy-lation in the atmosphere was a primary process for the removal of PCBs from the environment. It was later shown that the products were chlorinated benzoic acids produced by initial reaction with a hydroxyl radical at the 1-position followed by transannular dioxygenation at the 2- and 5-positions followed by ring fission (Brubaker and Hites 1998). Reactions of hydroxyl radicals with polychlorinated dibenzo[l,4]dioxins and dibenzofurans also play an important role for their removal from the atmosphere (Brubaker and Hites 1997). The gas phase and the particulate phase are in equilibrium, and the results show that gas-phase reactions with hydroxyl radicals are important for the... 

Scholer HF, Nkusi G, Niedan VW, Muller G, Spitthoff B (2005) Screening of Organic Halogens and Identification of Chlorinated Benzoic Acids in Carbonaceous Meteorites. Chemosphere 60 1505... 

Siciliano, S. Germida, J. Degradation of chlorinated benzoic acid mixtured by plant-bacteria associations. Environ. Toxicol. Chem. 1998, 17 (4), 728-733. 

Still another possibility involves the solvated electrons mentioned previously. Most, if not all, of the demonstrated photoreduction reactions of pesticides in water take place with substances likely to form hydrated electrons—e.g., NAA, fenac, the phenoxyacetic acids, and the chlorinated benzoic acids. Although they have measurable independent lifetimes, hydrated electrons eventually undergo reactions such as those shown in Equations 5, 6, 7, and 8 ( 34,56). 

Figure 4. Catabolic pathways for degradation of chlorinated benzoic acids...

Chlorinated benzoic acids have been shown to be intermediates in the biodegradation of several chlorinated aromatic compounds, for example, 4-chlorobenzoic acid is formed in the biodegradation of both polychlorinated biphenyls [103]. Mixed microbial cultures, which have been studied by a number of groups under aerobic conditions, can degrade a wide range of chlorinated benzoic acids, including 2-, 3- and 4-chlorobenzoic acid as well as 3,4-dichloro- and 2,4-dichlorobenzoic acid [104]. By contrast, under anaerobic conditions, only reductive dechlorination of meta-substituted benzoic acids has been observed [49,105,106]. Cometabolism of chlorobenzoic acids in the presence of unsubstituted benzoic adds leads to the formation of the corresponding... 

Storage Store in tightly closed container under inert atmosphere store refrigerated Uses Intermediate in mfg. of chlorinated benzoic acids and benzoyl chlorides Manuf./Distrib. Aldrich http //www.sigma-aldrich.com] Bayer http //www.bayerus.com] Esprit http //www.espritchem.com] lhara Chem. Ind. UK TCI Am. http //www.tciamerica.com 3,4,a,a,a-Pentachlorotoluene CAS 13014-24-9... 

Storage Store in tightly closed container under inert atmosphere store refrigerated Uses Intermediate in mfg. of chlorinated benzoic acids and benzoyl chlorides Manuf./Distrib. Aldrich http //www.sigma-aldrich.com] Esprit... 

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