title: Synthesis of coplanar PCT as reference substances for the residue analysis of polychlorinated terphenyls.
abstract: In the course of the development of a new and reliable analytical method for the PCT, a group of environmental contaminants, six coplanar terphenyl congeners were synthesized and characterized by means of spectroscopic methods. These congeners are 3,3″,4,4″,5-pentachloro-p-terphenyl, 3,3″,4,5,5″-pentachloro-p-terphenyl, 3,3″,4,5″-tetrachloro-m-terphenyl, 3,3″,4,4″,5-pentachloro-m-terphenyl, 3,3″,5,5',5″-pentachloro-m-terphenyl, and 3,3″,4,4″,5,5″-hexachloro-m-terphenyl. A combination of silica gel column chromatography and preparative NP-HPLC was successfully applied for the first time for the isolation of especially the asymmetrically chlorinated target compounds from product mixtures of the syntheses. For the 29 coplanar, tetra- to heptachlorinated meta- and para-indicator congeners which are envisaged to be used within the analytical method, a simplified systematic nomenclature is suggested. Furthermore, calculation results for all torsion angles of the preferred conformations of the substances are given. The practical relevance of the calculated conformation optima is exemplarily demonstrated by the chromatographic behavior of the PCT compounds.
authors.affiliation: Technische Universität Braunschweig, Institute of Environmental and Sustainable Chemistry, Hagenring 30, 38106 Braunschweig, Germany. Electronic address: hu.wichmann@tu-bs.de.
authors.forename: H
authors.initials: H
authors.lastname: Wichmann
authors.affiliation: Technische Universität Braunschweig, Institute of Environmental and Sustainable Chemistry, Hagenring 30, 38106 Braunschweig, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Schäfer
authors.affiliation: Technische Universität Braunschweig, NMR Laboratory of the Chemical Institutes, Hagenring 30, 38106 Braunschweig, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Ibrom
authors.affiliation: Technische Universität Braunschweig, Institute of Environmental and Sustainable Chemistry, Hagenring 30, 38106 Braunschweig, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Jüttner
authors.affiliation: Technische Universität Braunschweig, Institute of Environmental and Sustainable Chemistry, Hagenring 30, 38106 Braunschweig, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Saatz
authors.affiliation: Technische Universität Braunschweig, Institute of Environmental and Sustainable Chemistry, Hagenring 30, 38106 Braunschweig, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Vogt
authors.affiliation: Technische Universität Braunschweig, Institute of Environmental and Sustainable Chemistry, Hagenring 30, 38106 Braunschweig, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Bahadir
mesh_terms: D004785:Environmental Pollutants / Q000032:analysis* / Q000138:chemical synthesis* / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011080:Polychloroterphenyl Compounds / Q000032:analysis* / Q000138:chemical synthesis* / Q000737:chemistry; D012015:Reference Standards; D013329:Structure-Activity Relationship
chemical_list: D004785:Environmental Pollutants; D011080:Polychloroterphenyl Compounds
keywords: Analytical method development; Coplanarity; NMR analysis; PCT synthesis; Polychlorinated terphenyls; Suzuki coupling; Torsion angle calculation