Date of Award
Spring 5-2021
Degree Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
School
Mathematics and Natural Sciences
Committee Chair
Matthew G. Donahue
Committee Chair School
Mathematics and Natural Sciences
Committee Member 2
Julie A. Pigza
Committee Member 2 School
Mathematics and Natural Sciences
Committee Member 3
William Jarrett
Committee Member 3 School
Polymer Science and Engineering
Committee Member 4
Karl J. Wallace
Committee Member 4 School
Mathematics and Natural Sciences
Committee Member 5
Jacques K. Kessl
Committee Member 5 School
Mathematics and Natural Sciences
Abstract
This three-part dissertation is connected by the thread of utilizing sulfur-based functional groups, hence the power of sulfur. The first project was the development of a pentafluorobenzene based isothiocyanate chiral derivatizing agent (CDA), a class of compounds that differentiate enantiomers through covalent bond formation. This project, which was addressed using a combination of synthetic and computational methods and NMR analysis, gave rise to an CDA that was highly selective for amines and computationally predictable. Branching off of that, the second project demonstrated the use of two thioamide chiral solvating agents (CSAs), which had never been reported as a core functional group despite having favorable hydrogen bonding properties. By utilizing a series of NMR titrations of the analytes, either amide or mandelic acid, with the CSA. Both thioamide chiral solvating agents produced greater resolution than the well-known Kagan’s amide CSA, increasing the resolution of the enantiomeric pairs by 1H NMR up to 5x. CSAs without the hydrogen bonding capabilities or π acidic/basic pairing demonstrated poorer resolution. As a completely separate project, the use of computation to predict the crystal structures of sulfonamides, a well-known functional group was also started and so far, has shown that there is the potential for this to be viable for predicting the geometries of theoretically synthesizable sulfonamides, judging by the overall small errors observed for the dihedral angles, angles, and interatom distances observed between the crystal and computed structures for the sulfonamide core. Overall, these three projects display that, though much is known about these three sulfur-based functional groups, there is still much to learn about them and the manners in which they can be utilized.
ORCID ID
0000-0003-3839-7579
Copyright
Crull, 2021
Recommended Citation
Crull, Emily B., "The Power of Sulfur: A Study of an Isothiocyanate Chiral Derivatizing Agent, Thioamide Based Chiral Solvating Agents, and the Geometry of Sulfonamides" (2021). Dissertations. 1879.
https://aquila.usm.edu/dissertations/1879