Novel approaches to metal free catalysis

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The research proposed here will explore boron architectures to develop innovative catalytic processes that offer unique reactivity not accessible to transition metal (TM) catalysts, notably in C-H functionalization processes. Our long-term goal is to refine this knowledge to develop unique catalytic concepts that will simplify catalyst development and for catalytic processes that will be readily usable by end users (academic and industrial researchers) at a minimal cost, while respecting the guidelines of green chemistry (solvent-free, no toxic by-products, simple synthesis). The first theme will involve developing the transfer borylation reaction to carry out the C-H borylation of alkenes and apply this method to generate interesting chemical motifs. The transfer borylation, a reaction we developed in our research group, consists in using one expendable arylboronate (Ar-B(OR)2) to borylate an arene (Ar'-H), releasing Ar-H and Ar'-B(OR)2. By avoiding species with B-H bonds during catalysis, we can borylate substrates that are otherwise challenging to borylate using traditional catalysts, such as the ones containing alkene, alkyne or carbonyl moieties. We also want to exploit the equilibrium observed between two different arylboronates in solution to design active boronate reagents that would increase the catalytic activity when used in substoichiometric amounts. In the second theme, we will develop algorithms that will allow a combinatorial computational approach to frustrated Lewis pair (FLP) chemistry and catalysts' discovery. Using our knowledge on the computational design of frustrated Lewis pair catalysts and localization-delocalization matrices, we will determine invariants that will describe the electronic and steric properties of FLPs. We will develop an algorithm that will use a database made of these invariants that will predict the nature of the interaction between a Lewis acid and a Lewis base and quickly predict the FLP reactivity of possible Lewis pairs. This method will be calibrated using calorimetric studies that we will carry out in our laboratory. The last theme consists in coordinating FLPs on carbon electrodes to modulate the electronic properties of catalysts without requiring structural modifications. We want to demonstrate that electrochemistry can be a tool to help quantify the steric hindrance of FLPs and modulate their reactivity. We will notably graft C-H borylation catalysts to look at the effect of electronic modulation on catalysis. We will also develop an electrochemical approach to quantify the steric properties of FLPs.