Sterically Encumbered Guanidinates for the Kinetic Stabilization and Study of Terminal Iron Nitrides in Weak Ligand Fields

University Of Texas At El Paso, El Paso TX

Investigators

Abstract

In this project, funded by the Chemical Synthesis Program of the Chemistry Division, Professor Skye Fortier of the Department of Chemistry at the University of Texas at El Paso (UTEP) is investigating the synthesis and reactivity of complexes that contain iron bound to nitrogen (iron nitrides). In both nature, and in industry, iron nitrides play a fleeting but critical role in capturing nitrogen from the air that we breathe and transferring it to important species (such as fertilizers for crop growth) ? a process known as nitrogen fixation. Despite the importance of iron nitrides in the global nitrogen fixation cycle (and in the marketplace), the study of molecules possessing individual iron nitride units has been hampered by the lack of model complexes. This project is developing new molecular architectures to access, trap, and study reactive iron nitride compounds. The goals are to shed light on the steps of the nitrogen fixation cycle and to use lessons learned to develop important, new nitrogen complexes using earth-abundant iron. Importantly, this chemistry utilizes iron which is a sustainable, non-toxic metal ? avoiding the need for costly and toxic precious metals. This project provides research opportunities for early-career scientists, including students from historically underrepresented groups. UTEP is a minority serving institution with an 80% Hispanic student population. The training and development the students receive is critically important for preparing the next generation of domestic science and technology personnel capable of competing in the global marketplace. On top of this, in an effort to encourage an active role in their learning, a student-directed seminar involves students in the hosting and organization of departmental seminars twice per semester. This program includes an ?Ask Me Anything? interview session where the students can learn from the life and professional experiences of the guest speaker as a professional development exercise and to reinforce resiliency and fortitude as traits for success. This project involves the use of "super bulky" guanidinate ligands to kinetically stabilize reactive iron-nitride compounds and delves into the factors that affect iron nitride reactivity. Using redox chemistry and ligand modifications, structure-function relationships are examined as they pertain to the electronics and chemical behavior of the iron-nitride moiety. A goal is to modulate the reactivity of the iron-nitride unit through ligand field effects, effectively using the ligand as a "chemical remote control" to influence the nucleophilicity/electrophilicity of the nitride group. A new professional development program at UTEP was initiated to better prepares the next generation of science and technology personnel. Students have an active and dynamic role in their education through the student-directed seminar program.