Grant: Canada Research Chairs

N-heterocyclic carbenes (NHCs) are a unique class of molecule that have been known to form strong bonds to single metal atoms in transition metal complexes. This chemistry has been used to design catalysts that are highly active but retain stability due to the strong metal-carbon bond from the NHCs. The use of NHCs to modify bulk metal surfaces received considerably less attention prior to our 2014 publication and subsequent patent. In the last 6 years of the chair, we have demonstrated the generality and versatility of this technique, showing that NHCs bind to a variety of metals including gold, copper, silver, ruthenium, platinum and even graphene. We have carried out detailed microscopy studies with sub-molecular resolution providing insight into the relationship between NHC structure and monolayer stability/organization. We have also expanded into the use of NHCs to stabilize particulate metals, both metal nanoparticles and clusters. In these cases, the strong metal-carbon bonds confer considerable added stability to the nanomaterials. Through ligand design strategies, we have prepared materials that are chiral, and those that are able to be taken up by cells. In the coming years, we will expand our work on NHCs to include different types of bonding to the surface to optimize for different metals based on the electronic nature of the NHC. We will also design novel nanoclusters employing different metals and again optimize the NHC electronics. Finally, we will examine never-before employed synthetic methods that will provide new clusters, new insights into the mechanism of formation, and optimization of cluster properties (i.e. fluorescence and quantum yield). In the area of small molecule synthesis, our group has introduced the use of sulfones as highly optimizable leaving groups (electrophiles) in cross coupling reactions of three-dimensional organic structures. This work enables the preparation of biologically active molecules like drugs and drug candidates with control over their three-dimensional structure. In the next term of this chair, we will employ state-of-the-art methods to prepare a variety of molecules that have controlled chiral structures and test these in our facilities at the ITbM in Japan. We will carry out kinetic studies that will enable us to understand how best to introduce chirality and three dimensionality and will work to optimize the reactivity of the sulfone structures.