ED Sciences Chimiques
Copper and Iron-Catalyzed Carboxylation Reactions of Carbon Dioxide with Alkynes and Their Derivatives
by Huili WANG (Institut des Sciences Moléculaires)
The defense will take place at 15h00 - Salle de conférence ISM , 3ème étage Est ISM, Université de Bordeaux, Bâtiment A12, 3ème étage Est, 351 Cr de la Libération, 33405 Talence
in front of the jury composed of
- Jean-Luc POZZO - Professeur - Université de Bordeaux - Directeur de these
- Stéphane GRELIER - Professeur des universités - Université de Bordeaux - Examinateur
- Jean-François HALET - Directeur de recherche - Université de Rennes - Rapporteur
- Renata LOPES MOREIRA - Professeure - Federal University of Viçosa - Rapporteur
The research presented in this doctoral thesis offers innovative, high-performance, and sustainable solutions to the major challenge of catalytically activating carbon dioxide (CO2) under mild operating conditions that adhere to green chemistry principles. Through the exploration of three complementary approaches, we have demonstrated that it is possible to eliminate the need for expensive noble metals by judiciously leveraging the unique properties of copper and iron. First, the use of copper sulfide (Cu2S) highlighted the unexpected potential of simple, self-supported, mineral-derived binary heterogeneous catalysts to operate at ambient temperature and pressure with excellent robustness. Second, the study of the homogeneous Fe(0)-phenanthroline system pushed the boundaries of first-row transition metal catalysis by establishing a direct correlation between ligand steric modulation, electronic spin-crossover phenomena, and CO2 fixation efficiency, thereby opening up a vast theoretical and experimental field. Finally, the development of the CuNP@ZIF-8 heterogeneous composite validated the concepts of cooperative catalysis and nanoscale confinement, wherein the porosity and chemical functionality of a metal-organic framework work in concert with nanoscale metal active sites to maximize yields while ensuring long-term recyclability. The prospects arising from this work are numerous. From a fundamental standpoint, the detailed understanding of the multi-spin-state mechanisms observed for iron paves the way for designing new ligands capable of even finer control over these electronic barriers. From an applied perspective, adapting these catalytic systems to other CO2-involved coupling reactions—or integrating them into continuous-flow processes—would pave the way for the viable, large-scale industrialization of these breakthrough technologies for a circular carbon economy.