Date of Graduation
8-2024
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Chemistry (PhD)
Degree Level
Graduate
Department
Chemistry & Biochemistry
Advisor/Mentor
Kilyanek, Stefan M.
Committee Member
Coridan, Robert H.
Second Committee Member
Wang, Feng
Third Committee Member
Zheng, Nan
Keywords
Catalysis; Electrochemistry
Abstract
Meeting rising demands for commodity chemicals while simultaneously easing reliance on fossil fuels presents one of the most substantial challenges for chemistry to date. Biomass has emerged as a sustainable precursor to commodity chemicals but requires substantial deoxygenation to displace petrochemicals. Development of efficient catalysts to achieve these transformations remains one of the central goals of inorganic and organometallic chemistry. Electrochemical strategies to propel biomass conversion are attractive, providing the driving force for reactivity and insights into catalyst mechanism. This work focuses on proton-coupled electron transfer (PCET) to facilitate redox catalysis in biomass up conversion and homolytic bond cleavage in small organic molecules. For the first time, the deoxydehydration of vicinal diols to alkenes has been achieved without the use of sacrificial reductants. Reactivity is enabled by the electrochemical reduction of a Mo dioxo complex via PCET. Electrochemical PCET is also used to characterize the redox reactivity of a V dioxo complex. Understanding these redox properties uncovered the ability of the V dioxo complex to activate weak C-H bonds. Encouraged by the potent oxidizing power of metal oxo bonds, the electrochemical oxidative depolymerization of lignin to access valuable aromatics was targeted. The oxidation of lignin models was studied utilizing PCET to generate highly oxidizing Ru oxo complexes. Seeking to understand possible C-H activation pathways that enabled depolymerization of lignin generated interest in organic bond activation and functionalization. To achieve these oxidations electrochemically, a series of Ru complexes with distal basic sites were employed and their multisite PCET behavior was studied using electrochemical methods.
Citation
Canote, C. (2024). Proton-Coupled Electron Transfer to Drive Biomass Conversion. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/5403
