Design, Synthesis, and Characterization of Porphyrin Paddlewheel Frameworks
Document Type Article
A DISSERTATION Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Doctor of Philosophy, Major: Chemistry, Under the Supervision of Professor Wonyoung Choe. Lincoln, Nebraska: December, 2010
Copyright 2010 Paul M. Barron
The topological control of metal-organic frameworks (MOFs) has been of particular interest in materials research due to the exciting applications in hydrogen storage and catalysis. MOFs consist of organic linkers and metal nodes. The metal nodes are connected via coordinating bonding to organic linkers, resulting in a wide range of one, two, and three dimensional topologies. The applications of MOFs can be enhanced by the incorporation of open metal sites into the framework. As a result, development of methodologies for the inclusion of various metal centers into MOFs is important.
One of these strategies, the incorporation of metalloligands, has lead to our development of a new class of MOFs, called Porphyrin Paddlewheel Frameworks (PPFs). Herein we demonstrate how the incorporation of a porphyrin metalloligand gives us the ability to control framework topology. In addition, we present strategies to design structures with a variety of unsaturated metal centers of the pore surface.
Chapter 1 provides a brief introduction into MOFs and the terminology used throughout the dissertation. Chapter 2 focuses on the synthesis and structural analysis of 3D PPFs, where the porphyrins are metallated in situ. Chapter 3 focuses on the development of heterometallic MOFs, in which the metal composition can be independently controlled. Chapter 4 shows the controlled assembly of PPFs independent of the metalloligand metal. Chapter 5 shows a stoichiometric approach to PPF assemblies. Chapter 6 discusses how changing the porphyrin symmetry affects the resulting PPF topology.