Seminar Abstract:

The catalytic activity of late metal imido and oxo complexes is commonly associated with two electron atom/group transfer reactions. We have found that the strongly donating bis(carbene)borate ligand platform expands the scope of iron imido and oxo chemistry, leading to new roles for these ligands in catalysis. In one example, the high spin (S = 2) state of an anionic iron(II) imido complex attenuates the iron-nitrogen multiple bond character, helping to create an unusually electrophilic imido ligand that has reactivity patterns akin to those of early transition metals. This complex is active in redox-neutral reactions that involve the cooperative action of iron and imido ligand, which enable catalysis involving bond rearrangement and isotope exchange reactions. For pyridine substrates, the regioselectivity of H/D exchange is dictated by the counter cation. In a second example, we observe O atom insertion from oxygen atom donors into the Fe-C bonds of low-coordinate organometallic complexes. This stoichiometric reactivity provides a foundation for the catalytic synthesis of phenols. Experimental and computational investigations implicate a mechanism involving rate-determining oxygen atom insertion into the Fe-C bond from an iron(IV) oxo intermediate. By contrast, analogous S and Se atom insertion catalysis does not involve a high valent intermediate.

Speaker Bio:

Jeremy M. Smith was raised in Benoni, South Africa. He completed both undergraduate and graduate studies at the University of the Witwatersrand (Johannesburg), where he obtained his Ph.D. in organometallic chemistry under the supervision of Neil J. Coville. Following stints with Russell P. Hughes (Dartmouth College) and Patrick L. Holland (University of Rochester), he started his independent career at New Mexico State University in 2003. He moved to Indiana University in 2013, where he is currently Professor of Chemistry. His research interests center on synthetic inorganic chemistry as applied to fundamental questions in structure and bonding, organometallic catalysis and electrocatalysis.