Specifically functionalized dendrimers for catalysis in special media / Massimo Petriccone  

Public ISBD Titre : Specifically functionalized dendrimers for catalysis in special media Type de document : texte imprimé Auteurs : Massimo Petriccone, Auteur ; Anne-Marie Caminade, Directeur de thèse ; Rosa Maria Sebastian Perez, Directeur de thèse Langues : Anglais (eng) Tags : DENDRIMERS  CATALYSIS  PERFLUORINATED  SUPERCRITICAL CO2 Résumé : "The presented research represents a comprehensive exploration of phosphorhydrazone (PPH) dendrimers, delving into their synthesis, functionalization, and catalytic applications, with a specific focus on para-substituted phenols for surface functionalization. The synthesis process entails a meticulous two-step reaction sequence, initiating from chlorinated phosphorus atoms in the core and progressing through substitution with 4-hydroxybenzaldehyde, ultimately culminating in dendrimer generation through condensation with MMHP(S)Cl2. To enable subsequent metal introduction were synthesized different phenolic derivates, alongside a model molecule designed to emulate iminophosphine reactivity while addressing phosphine oxidation concerns. The synthesis of bidentate phenols was described in detail, emphasizing the challenges faced and optimizations made, with a particular focus on the scalability of the procedures. The research also explores the modification of dendrimer surfaces to enhance solubility, with a specific emphasis on integrating perfluorinated ligands. Despite challenges in overall yield, alternative synthetic pathways were considered, resulting in the successful synthesis of phenols functionalized in the para position with alkylpolyfluorinated chains of varying lengths. Moving on to the characterization of PPH dendrimers, the study begins with the preparation of (1-methylhydrazineyl)phosphonothioic dichloride (MMHP(S)Cl2). Model molecules were synthesized to simulate PPH dendrimer surfaces, progressing to higher dendrimer generations. Distinctive features of PPH dendrimers, including their identification through 31P-NMR, were highlighted. A significant challenge in this phase involved ensuring the scalability of PPH dendrimer synthesis, which was successfully overcome. The research then shifts its focus to the precise functionalization of PPH dendrimers with previously synthesized phenolic substituents. The objective was to minimize di-symmetric substitution during the precise di-functionalization of the P(S)Cl2 function. Catalyst synthesis involved ligands with metal complexation for stability. Both precisely and stochastically substituted PPH dendrimers were successfully scaled up to the gram scale. In the final segment, the research delves into the catalytic activity of dendrimeric catalysts in various coupling reactions, both in organic and non-conventional solvents. Stille cross-coupling, Heck cross-coupling, and Suzuki coupling reactions were explored. The dendrimeric catalyst exhibited heightened activity in the Stille cross-coupling, showcasing a positive multivalence and generation dendritic effect. Despite insolubility in scCO2, the catalyst demonstrated activity for the Stille cross-coupling in heterogeneous conditions, emphasizing a positive generation dendritic effect. Additionally, the dendrimeric catalyst showed activity for the Heck cross-coupling in a biphasic fluorous/organic system. The study also addresses challenges associated with catalyst recovery in both organic and non-conventional solvents. Comparisons between precisely and stochastically difunctionalized dendrimers underscore positive multivalence and generation dendritic effects in specific reactions. Notably, higher activity of precisely substituted dendrimers from generation 1 to 3 compared to stochastically substituted homologues was demonstrated in the Stille cross-coupling. In summary, this research provides a thorough examination of dendrimer synthesis, functionalization, and catalytic applications, offering valuable insights and suggesting avenues for future refinement in sustainable catalytic processes." Document : Thèse de Doctorat Etablissement_delivrance : Université de Toulouse 3 en cotutelle avec Universitat autònoma de Barcelona Date_soutenance : 01/03/2024 Ecole_doctorale : Sciences de la Matière (SdM) (Toulouse) Domaine : Chimie Macromoléculaire et Supramoléculaire En ligne : https://theses.fr/2024TLSES048 Specifically functionalized dendrimers for catalysis in special media [texte imprimé] / Massimo Petriccone, Auteur ; Anne-Marie Caminade, Directeur de thèse ; Rosa Maria Sebastian Perez, Directeur de thèse . - [s.d.]. Langues : Anglais (eng) Tags : DENDRIMERS  CATALYSIS  PERFLUORINATED  SUPERCRITICAL CO2 Résumé : "The presented research represents a comprehensive exploration of phosphorhydrazone (PPH) dendrimers, delving into their synthesis, functionalization, and catalytic applications, with a specific focus on para-substituted phenols for surface functionalization. The synthesis process entails a meticulous two-step reaction sequence, initiating from chlorinated phosphorus atoms in the core and progressing through substitution with 4-hydroxybenzaldehyde, ultimately culminating in dendrimer generation through condensation with MMHP(S)Cl2. To enable subsequent metal introduction were synthesized different phenolic derivates, alongside a model molecule designed to emulate iminophosphine reactivity while addressing phosphine oxidation concerns. The synthesis of bidentate phenols was described in detail, emphasizing the challenges faced and optimizations made, with a particular focus on the scalability of the procedures. The research also explores the modification of dendrimer surfaces to enhance solubility, with a specific emphasis on integrating perfluorinated ligands. Despite challenges in overall yield, alternative synthetic pathways were considered, resulting in the successful synthesis of phenols functionalized in the para position with alkylpolyfluorinated chains of varying lengths. Moving on to the characterization of PPH dendrimers, the study begins with the preparation of (1-methylhydrazineyl)phosphonothioic dichloride (MMHP(S)Cl2). Model molecules were synthesized to simulate PPH dendrimer surfaces, progressing to higher dendrimer generations. Distinctive features of PPH dendrimers, including their identification through 31P-NMR, were highlighted. A significant challenge in this phase involved ensuring the scalability of PPH dendrimer synthesis, which was successfully overcome. The research then shifts its focus to the precise functionalization of PPH dendrimers with previously synthesized phenolic substituents. The objective was to minimize di-symmetric substitution during the precise di-functionalization of the P(S)Cl2 function. Catalyst synthesis involved ligands with metal complexation for stability. Both precisely and stochastically substituted PPH dendrimers were successfully scaled up to the gram scale. In the final segment, the research delves into the catalytic activity of dendrimeric catalysts in various coupling reactions, both in organic and non-conventional solvents. Stille cross-coupling, Heck cross-coupling, and Suzuki coupling reactions were explored. The dendrimeric catalyst exhibited heightened activity in the Stille cross-coupling, showcasing a positive multivalence and generation dendritic effect. Despite insolubility in scCO2, the catalyst demonstrated activity for the Stille cross-coupling in heterogeneous conditions, emphasizing a positive generation dendritic effect. Additionally, the dendrimeric catalyst showed activity for the Heck cross-coupling in a biphasic fluorous/organic system. The study also addresses challenges associated with catalyst recovery in both organic and non-conventional solvents. Comparisons between precisely and stochastically difunctionalized dendrimers underscore positive multivalence and generation dendritic effects in specific reactions. Notably, higher activity of precisely substituted dendrimers from generation 1 to 3 compared to stochastically substituted homologues was demonstrated in the Stille cross-coupling. In summary, this research provides a thorough examination of dendrimer synthesis, functionalization, and catalytic applications, offering valuable insights and suggesting avenues for future refinement in sustainable catalytic processes." Document : Thèse de Doctorat Etablissement_delivrance : Université de Toulouse 3 en cotutelle avec Universitat autònoma de Barcelona Date_soutenance : 01/03/2024 Ecole_doctorale : Sciences de la Matière (SdM) (Toulouse) Domaine : Chimie Macromoléculaire et Supramoléculaire En ligne : https://theses.fr/2024TLSES048

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