Mesostructured Hybrid Organic-Silica Materials: Ideal Supports for Well-Defined Heterogeneous Organometallic Catalysts

Engineering heterogeneous catalysts with molecular precision is an ongoing challenge to access materials with predictable properties that can be optimized using quantitative structure activity relationships. One approach is grafting organometallic complexes on dehydroxylated oxide supports using surface organometallic chemistry (SOMC). Although fruitful, this technique is limited to complexes containing a sigma-bound surface oxygen in the first coordination sphere of the metal. In this perspective, we describe our recent efforts to incorporate molecular diversity onto surfaces to obtain molecularly defined heterogeneous catalysts containing N-heterocyclic carbene ligands for C H activation, olefin metathesis, CO2 hydrogenation, and the Z-selective semihydrogenation of alkynes.