Synthesis and Characterization of 32 Polybrominated Diphenyl Ethers

Abstract

Polybrominated diphenyl ethers (PBDEs) are widely used as additive flame retardants in, for example, textiles, computers, television sets, and other electrical appliances. PBDEs are ubiquitous environmental contaminants, present also in humans. The environmental levels of the PBDEs are, however, still in general lower than those of polychlorinated biphenyls (PCBs). However, while the levels of PCBs generally are decreasing, those of the PBDEs are increasing in, for example, human milk. In the present study 32 individual PBDE congeners were synthesized and characterized. Physicochemical parameters including melting points and UV, 1H NMR, and mass spectra are reported. Twenty-nine monobrominated to heptabrominated diphenyl ethers were synthesized by the coupling between four diphenyliodonium salts and nine phenolates. One tetrabromodiphenyl ether and two hexabromodiphenyl ethers were synthesized by bromination of two different PBDEs. Twenty-one of the PBDEs and two of the iodonium salts, 2,2‘,4,4‘-tetrabromodiphenyliodonium chloride and 3,3‘,4,4‘-tetrabromodiphenyliodonium chloride, are to the authors' knowledge described for the first time. These synthesized reference compounds will aid in the identification and quantification of PBDEs present in environmental samples and will allow further assessment of PBDE toxicity.

In Vitro Estrogenicity of Polybrominated Diphenyl Ethers, Hydroxylated PBDEs, and Polybrominated Bisphenol A Compounds

“…The 17 PBDE congeners (> 98% pure; Figure 1, Table 1) were synthesized as described earlier (35,36). Three HO-PBDEs, 4-(2,4,6-tribromophenoxy)phenol (T 2 -like HO-BDE), 2-bromo-4-(2,4,6-tribromophenoxy)phenol (T 3 -like HO-BDE), and 2,6-dibromo-4-(2,4,6-tribromophenoxy)phenol (T 4 -like HO-BDE) ( Figure 1) were synthesized as described by Marsh et al (25) and were at least 99% pure.…”

Polybrominated diphenyl ethers and traditional organochlorine pollutants in fulmars (Fulmarus glacialis) from the Faroe Islands

“…Chemicals: The pesticide standards, hexachlorobenzene (HCB), 2,2-bis(4-chlorophenyl)-1,1-dichloroethene (4,4'-DDE), 2,2-bis(4-chlorophenyl)-1,1,1-trichloroethane (4,4'-DDT) and the individual PCB congeners (numbered according to (Ballschmiter et al, 1993) CB-53, CB-101, CB-105, CB-118, CB-128, CB-138, CB-153, CB-156, CB-170, CB-180, CB-183 and CB-200 were purchased from Larodan Fine chemicals AB, Malmö, Sweden). The individual PBDE congeners (also numbered according to (Ballschmiter et al, 1993) BDE-47, BDE-77 BDE-99, BDE-100, BDE-138, BDE-153, BDE-154 and BDE-209 were synthesized in house (Marsh et al, 1999;Örn et al, 1996)). All solvents were of pesticide analysis quality.…”

Human prenatal and postnatal exposure to polybrominated diphenyl ethers, polychlorinated biphenyls, polychlorobiphenylols, and pentachlorophenol.

“…BDE-17, BDE-28, BDE-47, BDE-66, BDE-100, and BDE-154 were synthesized as described elsewhere (Marsh et al 1999;Örn et al 1996). PCB congeners were purchased from Ehrenstorf (Augsburg, Germany).…”