Ligand topology tuning of iron-catalyzed hydrocarbon oxidations

Quite unexpectedly, the topology of the tetradentate ligand in [Fe^II-(bpmcn)(OTf)₂] (bpmcn = N,N′- bis-(2-pyridylmethyl)-N,N′-dimethyl-trans-1,2-diaminocyclohexane), whether cis-α or cis-β (see picture), determines the course of catalytic alkane hydroxylation and olefin oxidation reactions with H₂O₂, which afford products with varying stereo-selectivity and dramatically different sources of incorporated oxygen. These results demonstrate the exquisite role ligands can play in the fine tuning of the reactivity of an iron catalyst.