Chiral Porous Metal-Organic Frameworks as A Tunable Platform for Asymmetric Catalysis

University Of Chicago, Chicago IL

Investigators

Abstract

In this project funded by the Chemical Catalysis Program of the Chemistry Division, Professor Wenbin Lin at the University of Chicago is developing new types of solid catalysts that translate solution phase catalysis into the solid phase. The production of most commodity chemicals utilizes solid phase catalysts due to their efficiency in chemical usage and separation. Certain important chemicals presently are only made in solutions because solid phase catalysts for their synthesis are not known. These processes usually require lots of organic solvents and can be quite wasteful. In this research project Professor Lin is synthesizing new classes of solid phase catalysts based upon metal-organic frameworks (MOFs), materials that are built from organic molecules and the framework pieces and metal atoms as the connecting points. The materials are porous which enables molecules to move in and out of the structures, and by tailoring the metal atom connection sites, the researchers are dictating the types of catalysis that can occur within the material. By matching the structures of the metal atom sites to known solution phase catalysts, the researchers are creating MOFs that can perform the analogous solution phase reactions. The project is also integrating research, training and education. Graduate and undergraduate students participating in the research project are learning important research and communication skills. Professor Lin is also partnering with the Collegiate Partner Program to host Chicago area high school students for a research experience in the laboratory. Professor Lin is developing strategies to synthesize novel chiral MOFs based upon m-BINAP motifs with large open channels and pores and to study their activity as single-site solid catalysts for asymmetric catalytic reactions. The studies are focusing on: 1) tuning the effective reaction space of chiral, porous MOFs through the inclusion of mixed linkers; 2) exploring earth-abundant metal asymmetric catalysis and organocatalysis within the MOFs; 3) realizing asymmetric photocatalysis via photoactive multicomponent MOF assemblies; and 4) developing multifunctional MOF systems for asymmetric tandem catalysis. The ability to determine MOF structures precisely provides distinct advantages over many other types of heterogeneous asymmetric catalysts, because the catalytic activities/selectivities of the MOF can be approximated using a range of characterization methods and altered through the use of tailor-made building blocks. MOF-based single-site solid asymmetric catalysts have the potential to become cost-competitive heterogeneous catalysts and find application in fine chemical synthesis.