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Hydrogneation and hydrosilylation reactions catalized by manganese and rhenium complexes / Buhaibeh, Ruqaya  

Public ISBD Titre : Hydrogneation and hydrosilylation reactions catalized by manganese and rhenium complexes Type de document : texte imprimé Auteurs : Buhaibeh, Ruqaya, Auteur ; Yves Canac, Directeur de thèse ; Sortais, Jean-Baptiste, Directeur de thèse Année de publication : 2020 Langues : Anglais (eng) Tags : MANGANESE  RHENIUM  N-HETEROCYCLIC CARBENES  PHOSPHINES  LIGANDS  HYDROGENATION  HYDROSILYLATION Résumé : "Spectacular advances have recently been achieved in hydrogenation and hydrogen transfer reactions of unsaturated bonds catalyzed by well-defined Mn(I) complexes. My PhD work was divided into two main parts, the first part was devoted to the preparation of various Mn(I) complexes of easily accessible bidentate NHC-phosphine ligands, these complexes afforded valuable catalytic results in the hydrogenation of ketones. This catalytic process highlights a new mode of metal-ligand cooperation involving a non-classical metalla-substituted phosphonium ylide obtained upon C-H deprotonation of a chelating NHC-phosphine ligand in the Mn coordination sphere. The latter can easily activate H2, thus providing the first evidence of the involvement of ?5-phosphorous species in metal-ligand cooperation. In order to reach more active catalytic systems because of higher rigidity and robustness, next to the bidentate series, cationic NHC core Mn(I) pincer complexes based on a PCN and PCP ligands were also prepared and fully characterized. They were found to be less active in the hydrogenation of ketones compared to their bidentate analogues. The second part involved the reduction of carboxylic acid and esters with high chemo-selectivity to afford corresponding silyl acetals, which can then be easily converted into aldehydes by acid treatment. These transformations which do not require the presence of well-defined ligands were carried out using the commercially available Mn2(CO)10 and Re2(CO)10 pre-catalysts in the presence of triethylsilane as reducing agent under irradiation at room temperature." Document : Thèse de Doctorat Etablissement_delivrance : Université de Toulouse 3 Date_soutenance : 18/12/2020 Ecole_doctorale : Sciences de la Matière (SdM) (Toulouse) Domaine : Chimie Organométallique et de Coordination Localisation : LCC En ligne : http://www.theses.fr/2020TOU30234 Hydrogneation and hydrosilylation reactions catalized by manganese and rhenium complexes [texte imprimé] / Buhaibeh, Ruqaya, Auteur ; Yves Canac, Directeur de thèse ; Sortais, Jean-Baptiste, Directeur de thèse . - 2020. Langues : Anglais (eng) Tags : MANGANESE  RHENIUM  N-HETEROCYCLIC CARBENES  PHOSPHINES  LIGANDS  HYDROGENATION  HYDROSILYLATION Résumé : "Spectacular advances have recently been achieved in hydrogenation and hydrogen transfer reactions of unsaturated bonds catalyzed by well-defined Mn(I) complexes. My PhD work was divided into two main parts, the first part was devoted to the preparation of various Mn(I) complexes of easily accessible bidentate NHC-phosphine ligands, these complexes afforded valuable catalytic results in the hydrogenation of ketones. This catalytic process highlights a new mode of metal-ligand cooperation involving a non-classical metalla-substituted phosphonium ylide obtained upon C-H deprotonation of a chelating NHC-phosphine ligand in the Mn coordination sphere. The latter can easily activate H2, thus providing the first evidence of the involvement of ?5-phosphorous species in metal-ligand cooperation. In order to reach more active catalytic systems because of higher rigidity and robustness, next to the bidentate series, cationic NHC core Mn(I) pincer complexes based on a PCN and PCP ligands were also prepared and fully characterized. They were found to be less active in the hydrogenation of ketones compared to their bidentate analogues. The second part involved the reduction of carboxylic acid and esters with high chemo-selectivity to afford corresponding silyl acetals, which can then be easily converted into aldehydes by acid treatment. These transformations which do not require the presence of well-defined ligands were carried out using the commercially available Mn2(CO)10 and Re2(CO)10 pre-catalysts in the presence of triethylsilane as reducing agent under irradiation at room temperature." Document : Thèse de Doctorat Etablissement_delivrance : Université de Toulouse 3 Date_soutenance : 18/12/2020 Ecole_doctorale : Sciences de la Matière (SdM) (Toulouse) Domaine : Chimie Organométallique et de Coordination Localisation : LCC En ligne : http://www.theses.fr/2020TOU30234