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1.
Chemosphere ; 44(4): 671-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11482655

RESUMO

A new potential toxaphene congener 3-endo,5-endo-dichloro-7,7-bis-chloromethyl-4-dichloromethyl-tricyclo[2.2.1.0(2,6)]heptane 2 has been isolated from reaction mixture obtained by the chlorination of 2-exo, 10,10-trichlorobornane 1. The X-ray structural analysis of 2 revealed an unusual tricyclic structure, where the two chlorine atoms occupying endo-positions are in close spatial proximity with each other and near to the neighbouring CHCl2 group. Further, it revealed that the symmetry of the molecule is distorted. The 1H and 13C NMR spectra of 2 have been assigned by means of 1H, 1H double-quantum filtered correlation spectroscopy (DQF COSY), PFG 1H, 13C HMQC (pulsed field gradient heteronuclear multiple-quantum coherence), 1H, 13C heteronuclear multiple bond correlation (HMBC) experiments, and computer aided 1H NMR spectral analysis. The asymmetry of 2 is also discernible on the 1H NMR parameters. In addition, gas chromatographic (GC) properties and electron impact (EI) mass spectrum of 2 has been studied. Ab initio Hartree-Fock (HF) method with the basis set 6-31G(d) has been used for the optimization of the equilibrium geometry and calculation of total energy for 2. The optimized geometry is in good agreement with the crystal structure. According to the rotation energy profile calculated at the HF/6-31G(d) level, rotation of the chloromethyl and dichloromethyl groups are highly unlikely at the room temperature.


Assuntos
Inseticidas/química , Toxafeno/análogos & derivados , Poluentes Ambientais , Cromatografia Gasosa-Espectrometria de Massas , Inseticidas/síntese química , Espectroscopia de Ressonância Magnética , Modelos Teóricos , Temperatura , Toxafeno/síntese química , Toxafeno/química
2.
Chemosphere ; 37(2): 219-35, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9650265

RESUMO

Lipophilic organic compounds originating from kraft pulping and papermaking were identified by straight gas chromatography/mass spectrometry (GC/MS) analyses. Samples analyzed included a primary clarifier effluent (PE) and a secondary clarifier effluent (SE) from the activated sludge treatment plant of a Finnish ECF-bleached (Elementally Chlorine Free) kraft pulp and paper mill. Liquid-liquid extraction composition of PE was compared with solid phase extraction (SPE) and dialysis of a semipermeable membrane device (SPMD) exposed to PE. Dichloromethane extracts of particulate material isolated from PE, sludges from both the primary and secondary clarifier, a sediment collected in the vicinity of the mill and whitefish subacutely exposed to the secondary treatment effluent were also investigated. Typical pulp mill-related compounds such as terpenes, terpenoids and aromatic compounds were identified in PE whereas these were non-detectable in SE. For example, thunbergene, thunbergol, squalene, longifolene and derivatives of abietic acid were observed in PE. Alkylated polycyclic aromatics were major compounds identified in the sediment sample with retene (C4-alkyl phenanthrene) as a predominant component.


Assuntos
Terpenos/análise , Poluentes Químicos da Água/análise , Animais , Derivados de Benzeno/análise , Finlândia , Peixes , Cromatografia Gasosa-Espectrometria de Massas/métodos , Indústrias , Cloreto de Metileno , Papel , Fenóis/análise , Esteróis/análise
3.
Environ Health Perspect ; 60: 269-78, 1985 May.
Artigo em Inglês | MEDLINE | ID: mdl-3928353

RESUMO

Model compound studies which were previously done for impurities and environmental residues of chlorophenols and for wastes of chlorination processes were extended to the impurities and pyrolysis products of polychlorinated biphenyls (PCBs). Model compounds were commercial products or synthesized and their structures proven by spectroscopic methods. These models were used as analytical reference substances in GC/ECD and GC/MS studies of the pyrolyzed PCB samples. In addition to previously known neutral components like polychlorinated dibenzofurans (PCDFs), chlorophenolic substances, especially polychlorophenols (PCPs) and polychlorinated biphenylols (PCB-OHs) were observed as major pyrolysis products of PCBs. Capacitor fires are suggested to produce in many cases chlorophenols which are major toxic hazards to people.


Assuntos
Bifenilos Policlorados , Cromatografia Gasosa/métodos , Condutividade Elétrica , Incêndios , Cromatografia Gasosa-Espectrometria de Massas , Temperatura Alta , Bifenilos Policlorados/análise
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