Date of Award
Open Access Dissertation
Chemistry and Biochemistry
College of Arts and Sciences
Linda S. Shimizu
“Supramolecular chemistry” powered by non-covalent interactive forces forms the crux in the area of host-guest chemistry. Supramolecular assemblies often have different chemical and physical properties than that of its individual molecular entities and are used to develop novel functional materials. Our expertise involves making functional materials from macrocycles, which contain two urea groups and two rigid C shaped spacer groups. These individual macrocyclic components can self-assemble through hydrogen bonding and other non-covalent interactions to form porous supramolecular assemblies that can be used as confined reaction environments and as ligands to synthesize novel metal organic materials.
This dissertation focuses on studying the self-assembly, and the utility of three bis-urea macrocyclic systems, namely phenylethynylene, pyridine-phenylethylene, and bipyridine. My major research effort focuses on the scope and applications of the phenylethynylene bis-urea and its pyridine counterpart pyridine-phenylethylene macrocycles as confined environments for studying the absorption and diffusion of guests and investigating their reactivity in confinement. The second research project is based on bipyridine bis-urea macrocycle, which is a great candidate to study the architectures formed by interplay of metal ligand coordination and hydrogen bonds in the presence of suitable metallic guests. This dissertation consists of six chapters. The introductory chapter is devoted to discuss the structure and reactivity of organic solid-state host-guest systems as reaction media to carryout photoreactions. The work described in chapters two and three has been focused on our efforts to use phenylethynylene bis-urea as a nanoreactor to modulate [2+2] photodimerization of series of benzopyrones. We went beyond studying dimerizations with the reactor built from pyridine-phenylethylene bisurea where we were able to facilitate photoinduced polymerization reactions of isoprene which is detailed in chapter four. Chapter five describes the structure, electrochemistry and photophysical properties of an exo di-ruthenium complex synthesized using the bipyridine bis-urea macrocycle. It extends to a description of its application as a photosensitizer to carryout electronically mismatched Diels-Alder reaction of isoprene and trans-anethole using visible light. The chapter six reports the solid state structures and subsequent Hirshfeld surface analysis of 6-substituted chromones, which were used as guest molecules in chapter three.
Salpage, S. R.(2016). Synthesis And Utility Of Bis-Urea Macrocycles As Nanoreactors And As Ligands For Metal Organic Materials. (Doctoral dissertation). Retrieved from http://scholarcommons.sc.edu/etd/3749