Polyhalogenated Ethers

T0320 Funderburk Associates, Solidification Process T0355 Granular Activated Carbon (GAC)—General 

T0641 Radian International, L.L.C., Aquadetox/Soil Vapor Extraction (SVE) 

3M Company, 3M Empore Extraction Disk BioGenesis Enterprises, Inc., Soil and Sediment Washing Process Bioremediation Technology Services, Inc., BTS Method BioSystems Technology, Inc., Chlorinated Solvent Remediation (CSR) 

T0138 Calgon Carbon Corporation, Perox-Pure 

T0173 Commodore Applied Technologies, Inc., Solvated Electron Technology (SET) T0242 ELI Eco Logic International, Inc., Gas-Phase Chemical Reduction (GPCR) 

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Dichloroethyl, 1,1 ether under Dihalogenated and Polyhalogenated Ethers... 

Dichloromethyl, 1,1, Ether Methyl-dichloro-1,1 Ether under Dihalogenated and Polyhalogenated Ethers Dichlorophenol under Halophenols... 

Dichlorophenoxyacetic add 2,4-D under Carboxylic Acids with Other Functional Groups Dichloropropane, 1,2 under Saturated Alkyl Halides Dichlorotrifluoroethane HCFC-123 under Saturated Alkyl Halides Dieldrin under Dihalogenated and Polyhalogenated Ethers... 

Diethyl Benzene under Disubstituted and Polysubstituted Benzene Hydrocarbons Diethyl Ether under Noncyclic Aliphatic or Aromatic Ethers Dihalogenated and Polyhalogenated Ethers... 

Trichlorophenoxyacetic, 2,4,5 Acid under Dihalogenated and Polyhalogenated Ethers Trichloropropane, 1,2,3 under Saturated Alkyl Halides... 

In 1979, it was stated that poiybrominated aromatic ethers have received little attention (ref. 1). That statement is still applicable. Analyses to characterize this class of commercial flame retardants have been performed using UV (refs. 1-2), GC (refs. 1-6), and GC-MS (refs. 1-4). The bromine content of observed peaks was measured by GC-MS, but no identification could be made. The composition of poiybrominated (PB) diphenyl ether (DPE) was predicted from the expected relationship with polyhalogenated biphenyl, a class which has received extensive attention. NMR (refs. 3-6) was successfully used to identify relatively pure material which had six, or fewer, bromine atoms per molecule. A high performance liquid chromatography (HPLC) method described (ref. 1) was not as successful as GC. A reversed phase (RP) HPLC method was mentioned, but no further work was published. 

Anaerobic dehalogenation has also been observed in aromatic ethers including polychlorinated dibenzo[l,4]dioxins (Fennell et al. 2004 Yoshida et al. 2005). The anaerobic debromination of decabromodiphenyl ether is considered here since it is analogous to the dehalogenation of polyhalogenated biphenyls. 

Fig. 7 Generic chemical structures of polyhalogenated compounds. X=C1, Br. (I) Polychlorinated biphenyls (PCBs), polybrominated biphenyls (PBBs) (II) chlorophenols (CPs), bromophenols (BPs) (III) polychlorinated diphenyl ethers (PCDE), polybrominated diphenyl ethers (PBDE) (IV) polychlorinated dibenzo-p-dioxin (PCDD), polybrominated dibenzo-p-dioxin (PBDD) (V) polychlorinated dibenzofuran (PCDF), polybrominated dibenzofuran (PBDF) (VI) tetrabromobisphenol A (TBBPA)...

A silver-induced ring-opening reaction of various tri- and tetrahalocyclopropanes to produce polyhalogenated dienes or methyl polyhaloallyl ethers in good yields has recently been described [182] ... 

Multiple arylations of polybromobenzenes have been conducted to generate electron-rich arylamines. Tribromotriphenylamine and 1,3,5-tribromobenzene all react cleanly with A-aryl piperazines using either P(o-tolyl)3 or BINAP-ligated catalysts to form hexamine products [107]. Reactions of other polyhalogenated arenes have also been reported [108]. Competition between aryl bromides and iodides or aryl bromides and chlorides has been investigated for the formation of aryl ethers [109], and presumably similar selectivity is observed for the amination. In this case bro-mo, chloroarenes reacted preferentially at the aryl bromide position. This selectivity results from the faster oxidative addition of aryl bromides and is a common selectivity observed in cross-coupling. Sowa showed complete selectivity for amination of the aryl chloro, bromo, or iodo over aryl-fluoro linkages [110]. This chemistry produces fluoroanilines, whereas the uncatalyzed chemistry typically leads to substitution for fluoride. 

Fish-specific TEFs of halogenated diphenyl ethers have been low also in a rainbow trout early life stage mortality bioassay [85]. Halogenated diphenyl ethers were inactive in this bioassay, whereas polyhalogenated dibenzo-p-dio-xins, dibenzofurans, and biphenyls reduced growth and produced yolk sac edema and craniofacial malformations. PCDEs 71, 77, 102, 118, and 126 and PBDEs 47,85, and 99 were analyzed in this bio assay. 

Analytes CB, chlorobenzenes DDE, l,l-dichloro-2,3-bis(4-chlorophenyl)ethane DDT, l,l-dichloro-2,3-bis(4-chlorophenyl)ethylene DBF, decabromobiphenyls HBCD, Hexabromo-cyclododecane HpBB, heptabromobiphenyl PBB, polybrominated biphenyl PBCCH, pentabromochlorocyclohexane PBDE, polybrominated diphenyl ether PBT, Polybutylene terephthalate PCB, Polychlorinated biphenyl PBDD, polybrominated dibenzo-/ -dioxins PBDF, polybrominated dibenzofuranes PCN, polychlorinated naphthalenes PCP, polychlorinated phenols PBB, polybrominated biphenyl PeBDE, pentabromodiphenyl ether PET, Polyethylene terephthalate PXDDs, polyhalogenated dibenzo-p-dioxins PXDFs, polyhalogenated dibenzofurans TBBPA, tetrabromobisphenol A TBPA, tetrabromophthalic anhydride TCBPA, tetrachlorobisphenol A TDBPP, tris(2,3-dibromopropyl)phosphate. 

Atlas, E., K. Sullivan, and C. S. Glam. 1986. Widespread occurrence of polyhalogenated aromatic ethers in the marine atmosphere. Atmos. Environ. 20(6) 1217-20. 

Many mycotoxins, including the trichothecenes and fumonisins, have polar hydroxyl groups that can be readily derivatized to trimethylsilyl ethers with such reagents as trimethylsilyl chloride or hexam-ethyldisilazane and N-trimethylsilylimidazole. Alternatively, polyhalogenated acyl derivatives can be made, using reagents such as trifluoroacetic anhydride or heptafluorobutyric anhydride, which are especially useful in conjunction with the BCD. 

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