Recyclable Nanoparticles as Catalysts for Green Organic Chemistry

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The main goal of this research programme is to design new recoverable catalysts for efficient synthesis with minimal environmental impact. Catalysis is now almost universally used in chemical and petrochemical processes. A majority of these catalysts are heterogeneous in nature because they are easy to recover or utilize in flow processes. In this context, nanoparticles, which may combine high activity and selectivity with potential for recovery, appear as excellent candidates to bridge the gap between homogeneous and heterogeneous catalysis. However, their reactivity still remains to be explored at a fundamental level to understand the reaction mechanisms at play on their surface, to rationalize the selectivity observed, decipher homogeneous vs heterogeneous catalytic pathways and finally design dedicated catalysts. This programme is aimed at addressing these question. It is divided in 3 axes. In the first one, we will explore the catalytic activity of magnetic nanoparticles composed of reduced iron and copper or gold, for the Huisgen condensation and the oxidation of olefins respectively. We will also investigate the chemical reactivity of hollow spheres of iron oxide, a class of nano material with potential for the catalyzed oxidation of olefins. In a second axis, we will investigate the stabilization of iron nanoparticles in ionic liquids using functionalized ionic liquids. This class of nanoparticle stabilizers features an anchoring species, here a phosphine or a phosphinine, that can alleviate the tendency of iron to oxidize. These particles will be tested for the hydrogenation of olefin reaction and may afford cheap catalysts for the conversion of biomass to fuels. At last, we will explore the possibility of using cellulose nanocrystallites as chiral supports for heterogeneous enantioselective catalysis. Two approaches are described, one relying on the use of Pd nanoparticles, one on phosphoric acid based organocatalysts. In all cases the enantiomeric induction is provided by the surface of the CNC. These hybrids are separable using simple membranes. With skills ranging from nanoparticles synthesis and characterization, inorganic and organic synthesis to catalysis, HQP trained in this programme are ideally positioned to enter the job market.