The naphthalene diimide (NDI) nanotube is a self-assembly supramolecular system marked by intriguing properties and behaviour. The chirality of each NDI monomer determines the helicity of the nanotube, held together by non-covalent interactions and capable of reversible destruction and formation. The nanotube acts as a receptor for C<sub>60</sub> and many other molecular guests. The same NDIs can also assemble into a distinct hexameric receptor for C<sub>70</sub>. In this thesis, the central role of chirality in the NDI assemblies is explored. Chapter 1 provides a general review of supramolecular chemistry; of the non-covalent interactions behind the assembly of supramolecular systems; of examples of the sergeants-and-soldiers effect, in which chiral ‘sergeant’ monomers may impose a preferred supramolecular structure or achiral ‘soldier’ monomers; of other published nanotube-based systems. All that was known about the NDI nanotube prior to the commencement of this work is described. Chapter 4 explores the possibility of sergeants-and-soldiers behaviour in NDI nanotubes. New achiral NDI monomers are synthesised, and problems both synthetic and analytical are overcome. A solvent dependence is discovered and exploited. Finally, sergeants-and-soldiers behaviour is observed, with some achiral NDIs acting as superior ‘soldiers’ to others. The reasons behind this are considered and a theoretical framework outlined to explain these discoveries. The impact of mixed chiral/achiral nanotubes upon C<sub>60</sub> uptake is examined. Chapter 3 covers the synthesis of new monochiral NDIs, with one chiral and one achiral centre. The use of these NDI saws sergeants is examined, with some surprising results. The interaction of monochiral NDIs with C<sub>60</sub> and C<sub>70</sub> is also considered. In Chapter 4 the physical properties of the nanotube are investigated, with a range of experiments examining issues such as solvent dependence and majority-rules behaviour.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:596094 |
| Date | January 2011 |
| Creators | Anderson, T. W. |
| Publisher | University of Cambridge |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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