A novel strategy towards the catalytic hydroamination of alkenes: Exploiting geometrically constrained phosphorus(III) species for the activation of ammonia

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The catalytic utilization of ammonia for hydroamination of olefins represents one of the “Holy Grails” in modern catalysis which is typically dominated by transition metals. However, efficient activation of ammonia is severely hindered by favored formation of Werner-type amine complexes (M←NH3). Additionally, the N-H bond strength of over 100 kcal/mol is another obstacle to overcome for the direct incorporation of ammonia into organic molecules. In contrast, main group compounds capable of activating ammonia via N-H bond cleavage outnumber the reports for transition metals, representing a cost-efficient alternative.This proposal aims to develop novel strategies to activate ammonia by geometrically constrained phosphorus(III) compounds. Popular strategies in transition metal catalysis will be investigated to allow for catalytic incorporation of NH3 in unsaturated organic substrates, namely phosphorus-ligand cooperativity and utilization of redox non-innocent ligand platforms. Besides exploiting the vast library of tridentate, meridionally coordinating pincer ligands, uncommon donor moieties will also be evaluated to account for thermodynamic tuning of phosphorus centered redox chemistry.