Mechanistic Investigation of Photoredox Catalyzed Chemistry

Photoredox catalysis has changed the landscape of synthetic chemistry research in the last decade. However, the mechanistic studies on these reactions have been limited. Our lab focuses on establishing the kinetic and mechanistic underpinnings of photoredox and photosensitized chemical reactions using spectroscopic and computational tools. We use time resolved infrared and transient absorption spectroscopy spanning both ultrafast (fs) and slow (ns to ms) timescales to directly observe transient species in each reaction step. Through data analysis and kinetic modeling, we are able to quantify not just the photophysical characterstics of catalysts, but the rate limiting steps, reaction bottle necks. Moreover, how changing reaction parameters such as structural changes to the photocatalyst, addition of other reagents, and solvent environment change the outcomes of each reaction step enable us to build a strong structure-function correlation to aid optimized Photocatalyst and catalytical cycle design for the desired reaction outcome. We are currently investigating multiple classes of photoredox chemistry including photoinduced electron vs energy transfer pathways, spectroelectrochemical investigation of consecutive photoinduced electron transfer chemistry, donor-acceptor photoredox chemistry. Stay tuned for exciting results soon.