Research

Organic NLO Materials for Intense THz Generation

Organic non-linear optical materials (NLO) are often used to shift the wavelength or frequency of incoming light to different and often more desirable frequencies on the electromagnetic spectrum. In collaborative efforts between the Michaelis organic synthesis laboratory and the Johnson spectroscopy laboratory, we are developing new NLO materials for the conversion of IR to THz frequency light. THz spectroscopy is an emerging area of spectroscopy with many applications in scanning and sensing, imaging, and computing. We employ a combined data mining/computational approach to identify new organic materials capable of THz generation.

In the Michaelis laboratory, we synthesize these new materials, develop large-scale synthetic protocols, and optimize the growth and processing of large organic crystals. Students on this project learn skills in organic synthesis, crystal growth, and crystal cutting and processing. This team typically consists of chemists and chemical engineers working together to optimize new processes and techniques. These efforts often lead to the development of commercial processes and products that are later licensed to companies for sale.

Electrophilic Catalysis with Heterobimetallic Complexes

The Michaelis Lab is broadly interested in new strategies to tune the reactivity and selectivity of transition metal catalysts. Incorporation of an electron-releasing or electron-withdrawing transition metal “ligand” into a bimetallic complex can greatly influence the reactivity of the active metal center. In this manner, enhanced electrophilic and nucleophilic catalysts can be generated through incorporation of an “inorganic ligand,” while maintaining supporting ligands capable of inducing the appropriate selectivity for the desired reaction. The main goal of this project is to understand and utilize heterobimetallic interactions to generate highly active electrophilic transition metal catalysts for organic synthesis. This project will seek to employ heterobimetallic catalysts for the development of olefin activation and C–H functionalization reactions.

α-Helical Peptide Scaffolds as Modular, Tunable, Enzyme-Like Catalysts for Multistep Synthesis

The enormous breadth of chemical reactions performed in biological systems can be attributed to nature’s ability to construct highly ordered arrangements of catalytic functional groups, or enzyme active sites. In addition, many organisms have evolved the ability to assemble polyketide synthases (PKSs), or multienzyme complexes that are capable of performing multistep synthesis in a linear fashion. Chemists have tried to mimic nature’s efficiency by constructing multifunctional catalysts or by designing multicomponent reactions or multi-catalyst systems. What is still lacking is a system that mimics nature’s ability to form structurally precise collections of functional groups (active sites) in a modular fashion that enables not only catalysis but also multistep synthesis.

This project will investigate the use of short helical peptides to display catalytic functional groups in a stereo-controlled fashion to achieve enzyme-like catalysis. This template approach will provide a new strategy for catalyst design and optimization that takes advantage of substrate preorganization and proximity to improve catalytic activity. The helical scaffold will also make possible the design and construction of multifunctional catalysts capable of performing multistep synthetic processes.