Thomas L. Peters

Micro-scale bromination procedure for synthesis of “2,3,7,8-substituted” brominated dibenzo-p-dioxins and dibenzofurans from [13C]-labeled precursors

Abstract Brominated dibenzo-p-dioxin and dibenzofuran (BDD/BDF) isomers, specifically having from one to three halogens located in the 2,3,7,8-substituent positions, that are [13C]-labeled for use as analytical internal standards in mass spectrometric methods are not yet commercially available. Based upon the current availability of [13C]-labeled dibenzo-p-dioxin and dibenzofuran (DD/DF) precursors, we have developed a simple and efficient synthetic procedure which produces brominated congeners that are predominantly substituted in the 2,3,7, and 8-positions. The gas/solid reaction of vaporized precursor and surface-supported iron (III) bromide occurs rapidly (seconds) at temperatures ≥ 240°C and can provide total product yields in the range of ∼30 to 50 mole % for initial precursor amounts between ∼1 μg and 10 mg. In this paper we shall describe the utility of this approach to produce ∼5 μg quantities of [13C12]-2,7-dibromodibenzo-p-dioxin (27-DBDD) and [13C12]-2,8-dibromodibenzo-p-dioxin (28-DBDD).

The determination of 2,3,7,8-tetrachlorodibenzo-p-dioxin in treated wastewater

Abstract A procedure has been developed for the determination of low levels (parts-per-trillion) of 2,3,7,8-tetrachlorodibenzo- p -dioxin in treated wastewater. A combination of cleanup steps on silica, alumina, and reactant modified adsorbents yields a relatively interference-free residue when examined by gas chromatography/mass spectrometry in the selected ion monitor (SIM) mode of operation.