This research award in the Chemical Synthesis (SYN) program supports work by Professor Lawrence Que of the University of Minnesota to generate synthetic analogs of high-spin iron(IV)-oxo intermediates that serve as the key oxidants for many nonheme iron oxygenases. In contrast, the vast majority of synthetic oxoiron(IV) complexes described to date are low-spin, which DFT calculations predict to be much less reactive than their high-spin counterparts. To test the DFT prediction, Professor Que and his team will synthesize complexes with high-spin Fe(IV)=O units and characterize them by X-ray crystallography whenever possible and by a combination of spectroscopic methods in order to gain detailed insight into their geometric and electronic structures. The abilities of the high-spin complexes to oxidize substrate C-H bonds will be correlated with their properties and compared to those of low-spin Fe=O complexes to determine what factors control Fe=O reactivity. A greater understanding of such factors will be important for the development of more effective C-H bond oxidation catalysts.
Oxidation processes are important in biology and in industrial settings. Gaining insights into how Nature carries out the oxidation of C-H bonds efficiently has important ramifications in the design of oxidation catalysts for large scale chemistry that will be more energy efficient, more environmentally friendly, and less wasteful of our resources.
