Functionalized nanoparticles

The focus of the Glorius group within the structure of the SoN is on the selective synthesis and characterization of metal and metal oxide nanoparticles and their application in important, particularly asymmetric catalytic reactions.

Despite the advanced development of the field of asymmetric catalysis (Nobel Prize for Chemistry 2001), only very few of these reactions are applicable to an industrial environment/scale. Problems arise from high costs, an insufficient space-time yield, low robustness and range of applications as well as difficulties regarding purification and recovery/recycling. However, in the area of heterogeneous catalysis, which is in industrial terms very popular, asymmetric variations are missing. Responsible for that lack is the in many times little understanding of heterogeneous catalysis (black box system) and poor structural manipulability.

Nanoparticles (NPs) could represent an interesting approach to bridge homogeneous and heterogeneous catalysis. Due to the small particle sizes high surface area-to-volume ratios are available, which is the reason for the high chemical/catalytic activity. Moreover, NPs can be influenced in their structure either in the course of their synthesis or afterwards. Applying chiral organic molecules (chiral modifier) to change the surface and to yield efficient catalysts for asymmetric catalysis is, up to now, a rather young and less investigated field. The modifier should be strongly bound to the NP, enhance the catalytic activity (active principle) and based on an active interaction with the substrates result in high activities and enantioselectivities. Furthermore, ideally the NPs should be stable and not lose any metal which is the basis for a long-term recycling of the catalyst. In our work we aim for a systematic investigation of NP synthesis, different modifiers and reactions as well as the underlying mechanisms and thus promote this economically and ecologically highly important, rather young research field.

Relevant preliminary work:

1. Elucidating the binding modes of N-heterocyclic carbenes on a gold surface
   Bakker A, Timmer A, Kolodzeiski E, Freitag M, Gao H Y, Mönig H, Amirjalayer S,*Glorius F,* Fuchs H.* J. Am. Chem. Soc. 140, 11889-11892 (2018)
2. Versatile micropatterns of N-heterocyclic carbenes on gold surfaces: Increased thermal and pattern stability with enhanced conductivity
   Nguyen D T, Freitag M, Ruehling A, Körsgen M, Lamping S, Schaefer A H, Siekman M, Arlinghaus H F, Van der Wiel W G, Glorius F, Ravoo B J.  Angew. Chem. Int. Ed. 57, 11465–11469 (2018)
3. N-Heterocyclic Carbene-Treated Gold Surfaces in Pentacene Organic Field-Effect Transistors: Improved Stability and Contact at the Interface
   Lv A, Freitag M, Chepiga K M, Schäfer A H, Glorius F,* Chi L.* Angew. Chem. Int. Ed. 57, 4792-4796 (2018)
4. Molecular Adsorbates Switch on Heterogeneous Catalysis: Induction of Reactivity by N-Heterocyclic Carbenes
   Ernst J B, Schwermann C, Yokota G -I, Tada M, Muratsugu S,* Doltsinis N L,* Glorius F.* J. Am. Chem. Soc. 139, 9144-9147 (2017)
5. Tunable Heterogeneous Catalysis – N-Heterocyclic Carbenes as Ligands for Supported Heterogeneous Ru/K-Al2O3 Catalysts to Tune Reactivity and Selectivity
   Ernst J B, Muratsugu S,* Wang F, Tada M, Glorius F.* J. Am. Chem. Soc. 138, 10718-10721 (2016)