METAL-LIGAND COOPERATIVITY IN BASE-METAL CATALYSIS USING BIOINSPIRED NHC-TIOLATES LIGANDS

Work package:
Homogeneous catalysis is one of the main leverages in sustainable green chemistry to access innovative chemical processes and to achieve sustainable carbon-neutrality in energy applications. A great current challenge is the development of earth-abundant and eco-friendly first-row transition metal (base-metal) catalysts to supplant widespread use of noble metals. In this regard, Metal-Ligand Cooperativity (MLC) is an effective strategy to yield high-performing base-metal catalysts.[1] Despite remarkable progress during the last decade, the latter are usually based on expensive, potentially toxic phosphorus-based ligands, which may offset the beneficial use of first-row metals. On the other hand, sulfur-rich metalloproteins and metalloenzymes, containing a strongly covalent metal-thiolate or metal-sulfide bonds (M-S) in their active site, are ubiquitous in Nature. In this context and based on the great expertise of our group in the development of functionalized bicyclic N-Heterocyclic Carbenes (NHC),[2] we have recently developed the bifunctional thiolate-ImPy ligand (S-ImPy-Mes), which merges a p-extended, bicyclic imidazo[1,5-a]pyridine NHC scaffold (ImPy) with a biomimetic thiolato ligand.[3] This ligand already showed an original and interesting coordination chemistry and was proved to be redox non-innocent. The objective of the internship will be to further develop first-row transition metal complexes (Fe, Co, Mn, Ni) which use thiolate-NHC ligands for bifunctional catalysis. The activity of the complexes will be evaluated in hydrogen evolution reaction (HER), small-molecule activation and MLC catalysis for sustainable biomimetic processes