Template directed synthesis of molecular knots

Chapter 1 introduces some important ideas involved in topology and their relationship to molecules both synthetic and naturally occurring. It includes a review of the literature related to the synthesis of topologically complex molecules with particular emphasis on template directed methods and attempts at the preparation of molecular knots. Chapter 2 then introduces my strategy for synthesising molecular knots utilising metal-ligand coordination and templating aromatic interactions.
Chapter 3 outlines the preparation of some octahedral metal complexes and describes attempted direct macrocyclisation reactions to give access to molecular knots.
Chapter 4 discusses some model complexes that have been used to investigate the templating aromatic interactions that form a key component of the design strategy. The influence of solvent and temperature on interactions between strongly polarised aromatic rings are reported.
Chapter 5 then outlines a successful new knot synthesis. Bipyridine oligomers containing appropriate spacers spontaneously fold into a knotted structure in the presence of a metal ion. Detailed characterisation of the molecular knots obtained is provided as well as a discussion of the importance of the oligomer structure and the metal ion. Chapter 6 outlines the potential of these products as topological building blocks for the preparation of a variety of knotted structures and describes attempts to prepare a novel knotted structure which we have termed an overhand knot. Finally, the preparation in moderate yield of a molecular trefoil knot is presented.
Full experimental details are given in Chapter 7.