Repository logo
 

Self-Assembly of Enantiopure Subcomponents into Functional Metal–Organic Cages


Change log

Abstract

Metal–organic cages possessing enclosed cavities have been shown to bind guest molecules selectively and mediate catalysis with improved reactivity and selectivity, among other applications. However, the use of enantiopure metal–organic cages for enantioselective applications has been limited both due the difficulty in construction of enantiopure cages and subsequent utilisation of their largely pseudo-spherical cavities.

To expand the use of metal–organic cages to chiral systems, the work presented in this thesis aims to explore methods of controlling the stereochemistry of cages by incorporating enantiopure building blocks into the structures to synthesise enantiopure cages.

In chapter 2 and 3, an enantiopure subcomponent was synthesised and differing degrees of stereochemical control were exhibited in combination with different ligands. Crucially, an anthracene containing cage could be synthesised diastereoselectively. Through subsequent reaction with encapsulated fullerene C6o and PCBM respectively, covalently attached enantioenriched fullerene tris- and bis-adducts could be synthesised and subsequently retrieved from the cages through addition of a triamine.

The project in chapter 4 utilises an enantiopure intermediate, namely a partially disassembled C6o-cage adduct with three free amines for the construction of increasingly complex heterometallic and heteroleptic cages. Chapter 5 provides examples of other attempts using different enantiopure subcomponents for the construction of enantiopure cages, notably achieving a greater degree of stereochemical control for self-assemblies based on a terphenyl ligand previously shown to form a complex mixture of multiple cage diastereomers.

Taken together, the work presented in this thesis provides examples and insight into methods of controlling the stereochemistry of cages utilising enantiopure subcomponents. The utilisation of the enantiopure anthracene-containing cage showcases the potential of enantiopure cages for the enantiopure applications, here achieving the synthesis of otherwise inaccessible enantiopure fullerenes.

Description

Date

2023-06-01

Advisors

Nitschke, Jonathan

Keywords

chirality, coordination cage, fullerene functionalisation, supramolecular chemistry

Qualification

Doctor of Philosophy (PhD)

Awarding Institution

University of Cambridge