New Carbanion Rearrangement of Sulfur Compounds and Its Application Abstract This thesis reports the investigation of an unusual reversal in the metalation selectivity of alkyl aryl sulfones and sulfoxides and its application. Such compounds undergo initial directed ortho-metalation at −78 řC despite having an acidic α-hydrogen atom and the resulting aryllithiums rearrange subsequently completely to the initially expected α-sulfonyllithiums on warming. The scope and the limitations for this process were identified. Both carbanion types of sulfones were applied in reactions with various electrophiles. α-Lithiated sulfones generated upon the transmetalation process were used in Julia olefinations. A mechanistic study of the course of the transmetalation reaction is presented. The kinetics of the transmetalation were determined. Investigations concerning the concentration dependence, proton transfer equilibria between the different ortho-sulfonyllithium intermediates and crossover experiments provided the evidence that a concerted intermolecular pathway prevails. On this basis a new integrated synthetic approach to naturally occurring iridoids was developed. It is based on a tandem alkoxycarbonylation/oxidative radical cyclization of the olefins synthesized by the Julia reaction after the investigated...

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Sulfonated polysulfone has been shown to possess desirable physical properties for use as a reverse osmosis desalination membrane. In this work, an extensive of dense membranes made from sulfonated polysulfone having 0.2, 0.4, 0.5, 0.6, 0.8, and 1.0 degree of sulfonation is described. The degree of sulfonation (D.S.) was maintained during the membrane fabrication process as evidenced by IR analysis. The effect of the degree of sulfonation and the counter ion, namely Na and K, on the properties of the membrane were examined. The hydrophilic nature of the material increased with increasing degrees of sulfonation, as evidenced by water uptake and the contact angle of water on the membrane surface. The amount of water increased from 0.6% for polysulfone to 19.2% for sodium salt of sulfonated polysulfone with D.S. of 1.0, and 12.2% for potassium salt of sulfonated polysulfone with D.S. of 1.0. The contact angle of water on polysulfone membranes was 75.1°. The contact angle of water decreased to 25.5° and 60.3° for sodium and potassium salt of sulfonated D.S. = 1.0) polysulfone, respectively. The decrease in the contact angle of water indicated an increase in the hydrophilicity of the membrane surface. Both the water uptake study and the contact angle measurement indicated greater hydrophilicity for the sodium salts of sulfonated polysulfone when compared to the potassium salts of sulfonated polysulfone for a given degree of sulfonation. The nature of the water within the membrane was found to be less hydrogen-bonded when compared to the bulk water. The surface of the membrane and the polymer powder was found to be different by ESCA analysis, and were also different from the bulk of the material. Neither the membrane surface nor the polytner powder surface had the same stoichiometry as the bulk. Ion exchange occurred not only on the membrane surface, but extended into the bulk with an overall ion exchange of about 80%. Electrical properti.es of the membranes were investigated by measuring the partial ionic conductivity and the selectivity of the membrane. The electrolyte/membrane/ electrolyte system showed ohmic behaviour. The membrane potential difference under applied transient current was greatly dependent on the nature of the cation, whereas the nature of the anion had no effect. The activation energy had minimal dependence on the membrane thickness, but depended on the nature of the electrolyte system. The effective size of the ion-conducting channels seemed to increase with higher degrees of sulfonation, probably due to a swelling process. SEM photomicrographs were taken to study membrane morphology and, in some cases, performance as a reverse osmosis membrane could be predicted from the SEM photomicrographs . / Ph. D.

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.

Thèse doctorat : Sciences : Strasbourg 1 : 2006. / Titre provenant de l'écran-titre. Bibliogr. 4 p.

Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal

This thesis describes two experiments: one related to antihistamines, and the other related to antitubercular compounds.

Partially disulfonated poly(arylene ether sulfone) (BPS) membranes have shown great promise as robust, chlorine tolerant alternatives to the current polyamide materials as reverse osmosis desalination membranes for water purification. The random copolymers are synthesized by direct polymerization of a disulfonated monomer (3,3’-disulfonato-4,4’-dichlorodiphenyl sulfone (SDCDPS)) and other monomers (4,4’-dichlorodiphenyl sulfone (DCDPS) and 4,4’-biphenol (BP)). The sulfonation of the materials adds necessary hydrophilic character and adjusting the percent sulfonation of the material changes the water and salt uptake of the material. Additionally, sulfonation causes the membranes to be charged, making them ion exchangers in which anions are partially excluded from the membrane, thus affecting the partitioning of salt in the membrane. The amount of sodium chloride present in the membrane after equilibration with external soaking solutions of varying concentrations of sodium chloride was measured by measuring the amount of individual ions, i.e., the sodium cation and chloride anion, separately. One area in which this work is unique is that it sought to measure the concentrations of the ions independently of one another. The analysis of sodium and chloride has shown the concentration of sodium in the membrane to be significantly greater than that of chloride, where the uptake of chloride is the limiting factor in the uptake of sodium chloride. The trends in the concentrations as well as in the partition coefficients of the ions are consistent with Donnan Exclusion. / text

Au cours des dernières années, nous avons développé, au laboratoire, un outil puissant permettant de former des liaisons carbone-carbone, basé sur la chimie radicalaire des xanthates. La fonction dithiocarbonate est transférée sur le produit d'arrivée en fin de réaction. Dans ces travaux, nous avons montré qu'au lieu d'être un inconvénient, ce transfert était un excellent point de départ pour réaliser des réactions d'allylation radicalaire. La première méthode est basée sur l'utilisation de sulfones allyliques substituées en α. Contrairement aux stannanes, les allyl isopropylsulfones sont de très bons agents d'allylation, ne montrant aucune trace d'oléfine isomérisée. Cette méthode a permis l'introduction aisée de diènes et énynes skipped. Le système d'initiation triéthylborane/oxygène a permis de réaliser l'addition de divers xanthates sur des époxydes vinyliques à température ambiante. Des alcools allyliques, ainsi que des amines allyliques et des allènes ont pu être préparés. Un équivalent radicalaire de la réaction de Wittig a été développé et repose sur l'utilisation d'éthers de fluoropyridine. L'addition du bromure de vinylmagnésium sur divers aldéhydes et cétones, suivie de la substitution de la 2,6-difluoropyridine par l'alcoolate correspondant a permis la formation d'agents d'allylation très puissants. Un acide aminé portant un sucre sur sa chaîne latérale a ainsi été préparé. Finalement, la synthèse de 5-aryl-pipéridin-2-ones s'est avérée possible par un processus radicalaire basé sur la cyclisation sur l'aromatique de dérivés d'aniline. Les pipéridinones formées ainsi que leurs précurseurs bicycliques pourraient avoir des propriétés biologiques intéressantes.