Etudes théoriques et expérimentales de mécanismes catalytiques impliquant des complexes de métaux de transition du groupe 10 et de mécanismes réactionnels impliquant des composés du phosphore hybridé.

摘要

A precise understanding of the reaction mechanisms should allow further optimization of the chemical transformations, with for instance improvement of reaction yields and / or design of more efficient catalysts. In order to gain a good knowledge of these mechanisms, experimental studies, with in particular the isolation of key species, are of utmost importance. On the other hand, theoretical studies make it possible to gain access to reactions' thermodynamics and kinetics. We show in this thesis that the combination of both approaches allows for a precise understanding! of various reaction mechanisms. Based on this "theoretical and experimental" approach, the mechanisms of various allylation reactions were first determined. Specifically, the mechanism of the palladium and platinum catalyzed "nucleophilic" allylation of amines with allylalcohol was studied as well as the palladium catalyzed "electrophilic" allylation of aldehydes with allyltributyltin. These studies allowed for the determination of complete catalytic mechanisms which are sometimes in contradiction with mechanisms found in the literature. We then turned our attention to the palladium catalyzed trimerisation of arylisocyanates. This study leads to the proposition of a mechanism for this transformation. Finally, the third part of this thesis consists in the study of three non catalytic reactions, two of which are about the reactivity and synthesis of phosphinines and the last one is about the acylations of a phospharuthenocene.