Synthesis, structure and reactivity of d- and f-block metal-aluminium heterobimetallic complexes

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Monometallic single-site platinum group metal catalysts predominate the homogeneous catalysis landscape. Recently, polarized heterobimetallic complexes are challenging this classical paradigm as they are capable of delocalizing bond activation/formation over two metal sites, where only one metal is redox active. However, facile synthetic routes to effective mixed p-/d-block catalysts have not yet been realized. This project aims to address this synthetic challenge for complexes containing unsupported transition metal (TM), lanthanide (Ln) and actinide (An)-aluminium bonds, and by determining their electronic structures using state-of-the-art characterization methods, we will develop structure-guided reactivity profiles in order to exploit this class of complex in small molecule activation chemistry.To achieve this, the synthesis of Mg-Al and Zn-Al heterobimetallic complexes and these will be used to transfer the Al fragment to transition metals enabling the synthesis of new TM-Al complexes using a variety of TM precursors; rapid progress is ensured as these starting materials are readily, and often commercially available. Based on electronegativities, the new TM-Al complexes can be divided into two categories: 1) complexes containing a Al--TM-+ polarized bond; and, 2) complexes bearing a Al-+-TM - polarized bond. These different bonding scenarios will promote divergent reactivity and catalysis that will complement and contrast each other. Synthetic access to a diverse range of TM-Al complexes will allow us to assess the range of effects that a directly bonded Al center can have on heterobimetallic catalysis, from spectator ligands that do not participate in some reactions, to examples that tune the electronic properties of the TM, cooperatively engaging with TM centres to facilitate substrate activation