Date of Award
Master of Science
Dr. Michael Barcelona
Dr. Sherine Obare
Dr. Yirong Mo
Green solvent, water, lactone, N-heterocyclic carbine, characterization
Masters Thesis-Open Access
Given the declining state of the natural environment, identifying green methodologies in synthetic chemistry is becoming paramount. An under explored area of green chemistry, is the use of catalytic systems in green solvents. One interesting concept in green chemistry is the use of N-Heterocyclic Carbenes (NHCs) as organocatalysts.
Thiamine or vitamin B1 was one of the first NHCs recognized. Thiamine is required for carbohydrate metabolism and helps the cell produce adenosine triphosphate (ATP). Over the last 20 years NHCs have been found to be efficient catalysts in carbon-carbon bond forming reactions.
But to date, little research has been done exploring the use of NHCs in unconventional solvent systems. Typical solvents of choice for reactions involving a homoenolate anion with a Michael acceptor include dichloromethane, tetrahydrofuran or alcohols. Investigations into reactions regarding homoenolate anions with a Michael acceptor in newer green solvents has received little to no attention. I will show the formation of cyclic compounds, most notably γ-butyrolactone(GBL) rings using water as a solvent.
Characterization of lactone products will be completed by advanced computational methods using Gaussian View software suite. The optimized geometries of lactones are obtained from density functional theory(DFT) calculations; at B3YLP/6-31G + (d, p) level of theory.
Since the parent lactone structure GBL shows bio-activity and has been used as a recreational street drug, further characterization will include a toxicology report.
Kidd, "Characterization of γ-Butyrolactone Rings: A Computational and Toxicological Study" (2017). Master's Theses. 1128.