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This thesis is based on two seemingly different types of organic building blocks: orthoesters and all-cis multifluorocyclohexanes. However, both compound classes have in common: they have only recently been used for the supramolecular objectives of this thesis ��� self-assembly, anion and cation binding, and functional materials. The first part deals with the orthoester exchange. Orthoester exchange is an acid-catalysed dynamic covalent reaction between orthoesters and alcohols that was re-discovered six years ago in the Delius group. In 2015, Delius and coworkers demonstrated the application of the orthoester exchange to the self-assembly of small hosts for sodium ions. The first big goal of this thesis was to expand the scope of orthoester exchange to more complex architectures using different cations and anions and to use the lability of orthoesters to create new (bio)degradable polymers. The first project describes the self-assembly of orthoester cryptates using different alkali metal cations. We could demonstrate the adaptive behaviour of orthoester cryptands, obtained after metal-ion removal, via subcomponent exchange in response to the addition of alkali metal ions. The second project presents the development of the first-ever fluxional supramolecular system ��� ammonium orthoester cryptates ��� in which ammonium cation acts both as a catalyst for orthoester exchange and as a template, thus leading to constant intramolecular rearrangements. The fourth orthoester project describes the development of high-density polyethylene mimetics bearing labile orthoester groups that impart the ability to degrade in acidic medium. The second part describes pioneering studies on the supramolecular properties of all-cis 1,2,3,4,5,6-hexafluorocyclohexane. All-cis C6H6F6 is unique because it is the most polar aliphatic compound reported to date. Its high dipole moment allows to form strong dipole-dipole and dipole-ion interactions that are among the most important and abundant non-covalent interactions. However, until 2017 the synthesis of all-cis C6H6F6 had been extremely tedious, precluding nearly all experimental investigations. In the first project, we demonstrate moderate affinities of all-cis C6H6F6 in solution toward simple inorganic anions. In the second project, we present an unprecedented platform for living supramolecular polymerization based on all-cis C6H6F6 derivatives. |
