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This thesis is concerned with the design and synthesis ofnew acyclic and macrocyclic receptors for anion binding and templation. ' Chapter One: Provides an introduction to the field of supramolecular chemistry and the nature of non-covalent interactions. A discussion of host-guest chemistry, in particular that of anions together with underlying principles of molecular recognition is given. Self assembly and anion templated interlocked molecular architectures are also reviewed. Chapter Two: Describes the design and synthesis of new Schiff base and amine pyridyl containing acyclic transition metal based receptors. The synthesis of transition metal macrocyclic receptor analogues are also presented. Their anion binding properties are investigated using a variety of spectroscopic and electrochemical techniques. Chapter Three: Explores the synthesis of a range of new acyclic tetra-amide based receptors containing the 2,6-bis-amide pyridyl moiety. Their anion binding properties are investigated by IH NMR spectroscopy. The ability of the new receptors to form orthogonal molecular assemblies is then investigated. The chapter concludes with the attempted syntheses of ion-pair receptors incorporating the new tetra-amide based anion recognition motif with polyethers. Chapter Four: Details the synthesis and anion binding properties of a range of bisvinyl functionalised acyclic compounds containing a tetra-amide anion recognition site. A new type of macrocycle is subsequently synthesised by an anion templated ring closing metathesis reaction. The anion binding properties of the new macrocycle are then studied by IH NMR spectroscopy. Its ability to form chloride anion templated pseudorotaxanes is studied with the use of different potential thread molecules. Whether oxoanions could be used as potential templates for pseudorotaxane formation is also probed. Chapter Five: Reports the synthesis and characterisation details for all products and intermediates. Chapter Six: Provides supplementary experimental information.

The aim of this thesis is to explore the Schwartz reaction, a method for the catalytic dechlorination of polychlorinated biphenyls (PCBs). Chapter One introduces PCBs, their stability and industrial utility, their subsequent detection in the environment and concerns over their human health effects leading to a political will for remediation 0 of PCB contaminated land. Natural, physical, biological and chemical destruction methods o for PCBs are then reviewed. The chapter concludes by introducing the Schwartz reaction which uses CP2TiCh, NaBH4 and pyridine in diglyme to dechlorinate PCBs. Its advantages and disadvantages are highlighted. Chapter Two studies the mechanism of the Schwartz reaction using a variety of techniques. A DFT study is described, reaction conditions are explored and a proposed intermediate (Cp2TiHpyr) is isolated and characterised with the aid of deuterium labelling. A Schwartz reaction using CP2TiHpyr is carried out in an EPR tube, conclusions are drawn about the Ti(III) species present therein and a modified mechanism is proposed. Chapter Three tests a variety ofnew catalysts for dechlorination ofPCBs. The original CP2TiCh catalyst is altered by variation of the ligands and the metal and other new systems containing an '(Tl-arene)FeCp' moiety are tested. New catalytic systems are presented including precursor compounds which are air and moisture stable. Chapter Four investigates the removal of toxic pyridine as a requirement for the Schwartz reaction. Alternative bases are tested and conclusions drawn about the role of the base in the mechanism. Transition metal complexes are then prepared which incorporate an amine (NMe2 or NtBu) or pyridine functionalised arm into the ligand framework. lIB NMR spectroscopy is used to observe the amine'BH3 adducts present in the reaction mixture and provide new insights into the reaction mechanism. Chapter Five explores heterogenisation of the Schwartz reaction by synthesising a range of titanocene functionalised polystyrenes. These are characterised using solid state IH NMR (MAS), TGA and EDX. These solids are then tested for their catalytic activity. Experimental procedures are documented in Chapter Six and characterising data for all new or previously uncharacterised compounds are given in Chapter Seven. Asummary of all catalytic data from Schwartz reactions in this thesis is given in Appendix One. DFT, EPR and crystal structure data are given in the Electronic Appendix.

The main aim: of this project is to develop novel acyclic and macrocyclic hosts for the binding and fluorescent sensing of anionic guests in solution. In addition the use of these hosts in anion templated interpenetrated architectures was exploited. Chapter One introduces the field of supramolecular chemistry and gives a brief description of the non-covalent forces employed in supramolecular host design. A description of the areas of anion binding and the more sophisticated discipline of anion sensing is given. The Chapter concludes with a discussion of the phenomenon of selfassembly and in particular, details the advances in molecular templation that have revolutionised the synthesis ofmechanically interlocked systems. Chapter Two describes the synthesis of a range of indolo[2,3a]carbazoles through a 'one-pot' Fischer indolisation reaction and their subsequent functionalisation to give acyclic and macrocyclic receptors. Schiff base receptors capable of intramolecular hydrogen bonding were shown to have minimal anion binding. However, a bipodal amino receptor showed very high anion affinity. Chapter Three details the preparation ofnew 'off-on' fluorescent sensors for anions using anthracene PET based receptors. Various neutral and charged anion binding groups were appended to the anthracene including imidazoliums and pyridine bis-amide derivatives. Both the anion binding potential of these receptors and the ability of the anion to effect the fluorescence PET ofthe anthracene were investigated Chapter Four reports the use of fluorescent receptors in Chapters Two and Three as . threads in anion templated [2]-pseudorotaxanes. Sulfate successfully templated the formation of an indolocarbazole pseudorotaxane while chloride was used for the anthracene derivative. Each section culminates in the attempts to permanently interlock the structures as [2]-rotaxanes. Chapter Five reports the synthetic procedures used within the thesis.

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