Structural analysis of selected polychlorinated persistent organic pollutants (POPs) and related compounds

Abstract

Detailed structural data of persistent organic pollutants (POPs) are necessary for their toxicological studies and for a correct assessment or prediction of their degradation or accumulation in biota and environment. In the present investigation the structures of 25 POPs, including eight chlordane derivatives, seven polychlorinated dibenzothiophenes (PCDTs), and ten potential toxaphene congeners, were studied by means of one- and two-dimensional NMR spectroscopy. The 1H NMR spectral parameters were precisely evaluated by computer aided spectral analysis. In the case of PCDTs and toxaphene congeners, the structural analysis was supported by methods of quantum chemistty. In addition, two toxaphene structures were determined by single crystal X-ray analysis. Finally, two POP-related pentafulvalene derivatives were synthesized and their structures were elucidated by NMR and X-ray crystallography. In the literature section of the thesis, a review of the application of NMR to structural analysis of selected POPs (technical chlordane, PCDTs and toxaphene) is presented. In some cases quantum chemical and X-ray crystallographic studies are included. Finally, synthetic, NMR spectroscopic, and X-ray c1ystallographic investigations of pentafulvalene and its derivatives are briefly discussed.