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This dissertation details the synthesis and analysis of novel supramolecular species that feature simple fluorinated organomercurials, such as trimeric perfluoroortho- phenylene mercury ([o-C6F4Hg]3). These organomercurials can complex a variety of unsaturated substrates including arenes and alkynes. The major emphasis was on developing molecular architectures that are held together in part by secondary Hg-Calkyne interactions. Diphenylpolyynes, hydrocarbons featuring extended regions of unsaturation, were found to complex with [o-C6F4Hg]3 in a series of adducts. While the internal structures of the hydrocarbons themselves were found to be basically unaltered, within the crystals the polyynes were physically separated from one another by intervening molecules of [o-C6F4Hg]3, preventing them from cross-linking. This leads to a substantial stabilizing effect, for example [o-C6F4Hg]3 and Ph(CC)4Ph form a 2:1 adduct that is stable at temperatures up to 120 ºC above the pure hydrocarbon. Adducts of [o-C6F4Hg]3 and molecules containing a 1,3,5-triethynyl benzene core display a variety of novel properties. 1,3,5-tris(trimethylsilylethynyl) benzene forms binary supramolecular stacks with [o-C6F4Hg]3. The structure also displays large cylindrical 1-dimensional cavities. These cavities are lined with non-polar groups, have an internal diameter of 6.2 Å, and remain stable in the absence of guests. The compound readily interacts with and reversibly adsorbs simple alkanes. 1,3,5-tris(phenylethynyl) benzene forms similar stacks with [o-C6F4Hg]3, albeit without the cavities. Upon irradiation with visible and ultraviolet light, this adduct emits a long-lived emission that was hitherto unreported. From computer calculations and lifetime measurements, it appears this radiation is the phosphorescence of the pure hydrocarbon. Intensive structural studies have also been performed on adducts containing polyaromatic compounds, including phenanthrene, and the organomercurials [o- C6F4Hg]3, pentafluorophenyl mercury chloride and bromide. These experiments were performed to determine if Lewis acid-p complexes could be made with monofunctional mercury compounds. Polyaromatic hydrocarbons, such as phenanthrene and diphenylacetylene, were used as the substrates for these investigations. While all the mercurials formed adducts with the substrates, the photophysical measurements were not uniform and indicate that [o-C6F4Hg]3 has a stronger heavy-atom effect because of the cooperativity of the three mercury atoms.

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published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

Thesis (Ph. D.)--University of Hong Kong, 1996. / Includes bibliographical references.

Thesis (Ph. D.)--University of Chicago, 1919. / "Private Edition, Distributed by the University of Chicago libraries, Chicago, Illinois, 1921." "This Work was carried out in co-operation with Professor J.F. Piccard and published in J.Am. chem. soc., 40, 1074 (1918) and 42, 1855 (1920)" Includes bibliographical references. Also available on the Internet.

La Directive Cadre sur l'Eau (DCE) (2000/60) a mis en place une liste de 33 substances prioritaires, avec des normes qualité de l'environnement (NQE) pour chaque substance, et leur concentration dans les milieux aquatiques qui ne doivent pas dépasser c es NQE. De plus, elle exige des performances analytiques spécifiques pour ces méthodes: la limite de quantification doit être au moins aussi basse que 30% des NQE et l'incertitude de la méthode au niveau de la NQE doit être inférieure à 50%, pour k = 2. Par conséquent, le défi analytique actuel est de mesurer de faibles concentrations de ces polluants dans les matrices parfois difficiles. Ceci peut être réalisé en améliorant la technique d'extraction utilisée pour obtenir un extrait de l'échantillon plus concentré et plus propre. Dans ce contexte, les trois méthodes d'analyse ont été mises au point pour déterminer les composés musqués, alkylphénoliques et organométalliques dans les matrices environnementales. Ces techniques d'extraction et de pré-concentration innovantes ont ensuite été appliquées pour l’évaluation de la présence de ces composés dans les stations d'épuration locales et dans les cours d'eau récepteurs. Enfin, les niveaux de concentrations de fond au niveau national ont été mises à jour pour les composés organométalliques. / The ambitious Water Framework Directive (WFD) (2000/60) set up a list of 33 priority substances, with Environmental Quality Standards (EQS) for each substance, and their concentration in aquatic environments should not go beyond the EQS. Additionally, it requires specific analytical method performances: the limit of quantification must be at least as low as 30 % of the EQS and the uncertainty of the method at the EQS level must be inferior to 50 %, for k=2. Therefore, the current analytical challenge is to measure low concentrations of these pollutants in sometimes difficult matrices. This can be achieved by improving the extraction technique used to obtain a more concentrated and cleaner sample extract. In this context, 3 analytical methods were developed to determine musk, alkylphenols and organometallic compounds in environmental matrices. Recent extraction and pre-concentration techniques were applied and later the occurrence of these compounds in the local WWTPs and in the receiving water bodies where they are discharged was evaluated. Additionally, updated French background concentrations were established for organometallic compounds.