This thesis explores the use of anions in the design and construction of interlocked architectures for applications in anion recognition and sensing, and to function as molecular machines upon a given stimulus. Chapter One introduces the field of anionic supramolecular chemistry focusing on host-guest chemistry and directed self-assembly. A review of the recognition and sensing of anionic guest species is given before strategies for the construction of interlocked architectures are discussed, and the potential functions of these structures considered. Chapter Two details the development of a novel anion-templation route for the synthesis of macrocycles and rotaxanes. The versatility of this route in constructing new [2]rotaxanes is explored by varying several features of the macrocyclic component, with emphasis on creating the most powerful anion complexant. Proton NMR spectroscopy is used to probe the anion binding properties of the rotaxanes, and X-ray crystallography and MD simulations are used to rationalize anion binding trends. The possibility of synthesizing catenanes for anion recognition via this new synthetic route is also investigated. Chapter Three investigates the appendage of transition metal complexes to rotaxanes to create interlocked host architectures capable of sensing anions via luminescence spectroscopy. The incorporation of rhenium(I) and ruthenium(II) polypyridyl complexes into the macrocyclic and axle component of [2]rotaxanes are described, before the anion binding studies of these structures using ¹H NMR and luminescence spectroscopy are reported. Chapter Four describes the strategic synthesis of [2]rotaxanes designed to undergo molecular motion upon a given stimulus. Initially, the possibility of exploiting anions to stimulate the macrocyclic component of the [2]rotaxanes to translocate to a second station on the axle is investigated. The use of pyridine N-oxide as an integrated template for rotaxane formation is reported before the ability of these rotaxanes to undergo anion and pH driven molecular motion is explored. This chapter concludes with the construction of a calix[4]diquinone N-oxide containing [2]rotaxane capable of undergoing sodium- and barium-induced molecular pirouetting. Chapter Five provides synthetic procedures and characterisation details for compounds listed in this thesis. Chapter Six reports supplementary experimental information including titration protocols, X-ray crystal structures and MD simulations.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:547595 |
| Date | January 2011 |
| Creators | Hancock, Laura M. |
| Contributors | Beer, Paul D. Beer |
| Publisher | University of Oxford |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://ora.ox.ac.uk/objects/uuid:d4f141f6-fd44-49cc-b14b-0dec22679c75 |
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