Asymmetric Heterogeneous Catalysis: Transfer of Molecular Principles to Nanoparticles by Ligand Functionalization

We demonstrate the functionalization of supported nanoparticles (NPs) with ligands as an approach to bridge the gap between homogeneous and heterogeneous catalysis. The use of chiral ligands is shown to allow for achieving stereoselectivity with supported catalysts. While these materials are considered to be very complex, we introduce a simple ligand reactant interaction model that can explain the origin of stereoselectivity on a molecular level. Application of general guiding principles from asymmetric homogeneous catalysis to our model allows for enhancing stereoselectivity in a rational manner to an enantiomeric excess of 74%. This highlights the potential of the presented approach for asymmetric heterogeneous catalysis. In addition, we demonstrate the feasibility of combining this asymmetric control with our previously introduced molecular concept to tune chemoselectivity. In this way supported catalysts are transformed to be stereo- as well as chemoselective, which highlights the potential arising from the idea of transferring principles from molecular catalysis to heterogeneous catalysts.