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|All Authors / Contributors:||
Jean Philippe Goddard; Charles Mioskowski; Université de Paris-Sud.
|Description:||137 p. ; 30 cm.|
|Responsibility:||Jean Philippe Goddard ; sous la dir. de Charles Mioskowski.|
During this work, we developed a method of original synthesis allowing to lead mixtures of molecules of variable size with an aim of discovering new chelating molecules of cesium. This method utilizes a reaction of polyhomologation of borated compounds with the nucleophilic ones comprising a grouping leaving in alpha of the negative charge. We tested various families from nucleophilic like anions of sulfones, sulfonium ylides, anions of hydrazones, triméthylsilyldiazométhane and arsonium ylides. The first three families did not allow us to carry out reactions of polyhomologation. The triméthylsilyldiazométhane posséde not either the capacity to carry out reactions successive insertions but this property was exploited to propose a chemical conversion of olefinic hydrocarbon into alkylmethanol corresponding. The arsonium ylides made it possible to carry out reactions of polyhomologation with boronates and boranes. The alkylarsonium ylides were used to form polymers of controlled size having a ramification on each carbon atom of the principal chain. This type of polymer is not accessible by the current methods of polymerization. The allylarsonium ylides have a particular reactivity since the allyl boranes formed during the insertion reactions undergo a sigmatropic [1,3] rearrangement before reacting again with a ylide. It is thus possible to lead with polymers of big size to which the structure is close to that of the natural rubber. By this method it is possible to lead with linear or cyclic polymers. This method is currently under development at the laboratory to form chelating structures of cesium.