High-Valent Nonheme Iron-Oxo Complexes: Synthesis and Reactivity

University Of Minnesota-Twin Cities, Minneapolis MN

Investigators

Abstract

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.