In this project funded by the Chemical Catalysis program of the Chemistry Division, Prof. Seth Cohen of the University of California, San Diego seeks to develop high value catalysts using metal-organic frameworks (MOFs), which are a type of porous solid. By incorporating metals into the MOFs very robust selective catalysts can be developed. (Catalysts are species that facilitate chemical processes, thus saving energy and time.) Catalysis is needed for activities ranging from pharmaceutical synthesis to advanced energy. The development of new catalysts that can perform important transformations and be readily separated from products, recovered, and recycled is of value for process efficiency and greener chemistry. The MOF-based catalysis developed in this project will help realize these goals. This proposal also includes teaching activities involving a Science Policy Internship Program (SPIP). The SPIP supports undergraduate STEM (science, technology, engineering, math) students at the University of California Center in Washington D.C. This program educates STEM students on the importance of science in pubic policy. This program has recruited both underrepresented and women students, across the University of California system, to help to create a generation of scientists that better appreciate their role in society and government.
The MOF materials targeted in this study are being developed to catalyze reactions where the advantages of a heterogeneous (i.e. solid state) catalyst can be exploited. In this study chiral substituents, organocatalytic groups, organometallics, and oxidizing metal centers are introduced into several known MOFs to produce single-site, catalytically active species. The project has three specific goals: 1. Modify the MOFs to generate organometallic active sites for transition metal catalyzed transformations; 2. Prepare MOFs that contain redox-active monocatecholato-metal sites that can perform oxidation reactions; and 3. Prepare MOFs with strong hydrogen-bonding groups, including squaramides, that can demonstrate significant organocatalytic behavior. These MOFs are attractive as catalysts because they can easily be isolated and separated from homogenous reaction mixtures by filtration, they contain well-ordered pores for potential size and shape selective reactions, and that they can be used to generate isolated active sites, reducing the chance of unfavorable interactions between catalytic sites.
