CAS: Properties and Activation Mechanisms of Mn-hydroperoxo and Mn-alkylperoxo Complexes

University Of Kansas Center For Research Inc, Lawrence KS

Investigators

Abstract

In this project, funded by the Chemical Structure, Dynamics & Mechanisms B Program of the Chemistry Division, Professor Timothy Jackson of the Department of Chemistry at the University of Kansas is developing and characterizing new manganese-hydroperoxo and manganese-alkylperoxo complexes that mimic important intermediates in several catalysts. The goal of this research is to understand how to control the reactions of these complexes, which could lead to the design of new catalysts. This research will also contribute to a better understanding of biological enzymes that use manganese. Manganese is an earth-abundant metal, and its increased use in catalytic reactions has the potential to mitigate some of the environmental impacts and costs of chemical processes. This project lies at the interface of inorganic and physical chemistry, providing a unique training experience for graduate and undergraduate students. Graduate students associated with this project will gain professional development skills, perform experiments at National Labs, and be involved in disseminating the outcomes of this work through peer-reviewed publications, conference presentations, and public events. Manganese-hydroperoxo complexes are proposed as intermediates in both biological and synthetic systems. Despite the importance of such intermediates, our understanding of the fundamental properties and reactivity of these complexes is in its nascent stages. In this project, a combination of synthetic, kinetic, spectroscopic, and computational methods will be employed to answer the following questions: 1) What are the fundamental physical properties of manganese(III)-hydroperoxo complexes, and how do these properties influence chemical reactivity? 2) Can we control proton and/ or electron delivery to manganese(III)-hydroperoxo and manganese(III)-peroxo complexes to initiate specific decay pathways? 3) Can we manipulate the coordination environment of manganese(III)-alkylperoxo complexes to influence the O-O bond cleavage mechanism? The new knowledge generated from this work will foster a better understanding of manganese enzymes and could yield principles for use in the design of new catalysts. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.