A molecular pentafoil knot and related circular helicates

Abstract

Knots are being discovered with increasing frequency in both biological and synthetic macromolecules and have been fundamental topological targets for chemical synthesis for the past two decades. However, only few synthetic molecular knots have been prepared to date and their properties remain largely unexplored. This thesis reports the synthesis of the most complex non-DNA molecular knot prepared to date: the self-assembly of five bis-aldehyde and five bis-amine building blocks around five metal cations and one chloride anion forms a 160-atom-loop molecular pentafoil knot (five crossing points).Chapter I aims to give the reader an overview of the current state of research in the field of template synthesis of molecular knots.Chapter II reports the synthesis and full characterisation of the most complex non-DNA molecular knot prepared to date, a pentafoil knot.Chapter III describes the synthesis of eleven pentameric cyclic double helicates derived from the scaffold of a pentafoil knot and presents an extensive study of the factors influencing the assembly process.Chapter IV reports the study of the self-sorting behaviour of a molecular Solomon link and a molecular pentafoil knot and their related non-interlocked systems. Chapter V the dynamic nature of pentameric circular helicates and a pentafoil knot is investigated, bringing insights on the subtle balance of thermodynamic and kinetic parametres involved in their self-assembly process.Chapter VI describes the halide binding properties of a synthetic molecular knot and doubly- and triply-entwined [2]catenanes based on circular Fe(II)-double-helicate scaffolds.

Date of Award	1 Aug 2016
Original language	English
Awarding Institution	The University of Manchester
Supervisor	David Leigh (Supervisor)