A Cooperative Approach to C-N Bond Formation

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Amines have found widespread applications in a range of industrial sectors including agrochemicals, food, textiles, plastics, and pharmaceuticals, where they make up approximately 20% of the top 200 best-selling pharmaceuticals and over 80% of drug candidates. The global market for amines in 2016 was estimated at $14.4bn USD and is projected to increase to $29.3bn USD by 2025 as demand for amine products significantly increases with the increase in world population. Traditionally, the synthetic supply of amines has been delivered by processes based on Hofmann alkylation, carbonyl-reductive amination, amide reduction and additions to activated imine derivatives. Recently, important advances in fields such as catalytic hydroamination, C-H amination and biocatalysis have significantly expanded the synthetic toolbox of amine-synthesis methods available to chemists. Despite this, the ongoing need for novel amines containing structures means the invention of new catalytic processes which directly convert readily available chemicals into complex amines has become an increasingly essential synthetic challenge. In this project, we will develop a transition metal FLP based on low-valent iron complexes bearing boron-based Lewis acid ligands, capable of participating in metal-ligand cooperativity. Given the importance of amines, this cooperative approach will be exploited in C-N bond formation reactions towards amine synthesis via N-H activation. The approaches outlined in this proposal offer a conceptually-distinct approach to two important synthetic routes towards amine scaffolds: 1) hydroamination - a reaction which typically occurs in the presence of Lewis acidic metals via pi-bond activation; and 2) N-aryl/alkylation - classically achieved via carbonyl reductive amination or metal-catalyzed cross coupling. Mild, catalytic approaches using earth-abundant elements towards the direct functionalization of N-H bonds are currently under explored, and the invention of robust and sustainable procedures to effect such transformations will constitute a step-change in the synthesis of amines.