Synthesis, Aggregation and Host Guest Properties of Water Soluble Macrocyclic Arenes

Resorcin[4]arene and pyrogallol[4]arene hydrogen-bonded hexameric capsules are well known supramolecular systems with potential applications in nanotechnology and biomedicine due to their host-guest properties in solution. However, to this day their remarkable host features are manifested solely in organic non protic apolar solvents non-competitive for hydrogen-bonding, thus limiting their applications in biological systems. To push forward this specific field of research, the present thesis aims to successfully design, synthesise and purify a new water-soluble pyrogallol[4]arene-based supramolecular derivative, allowing further investigations on its aggregation and molecular recognition properties in water. With this purpose a capsule-like structure bearing short aliphatic C6 hydrophobic portions and long methoxypolyethylene glycol (MPEG) chains as non-ionic hydrophilic pendants was obtained from acid-catalysed condensation of pyrogallol and a MPEG750-functionalized aldehyde. A similar acid-catalysed condensation of pyrogallol with 3,4-dihydropyran was applied to the synthesis of pyrogallol[4]arene-based scaffolds functionalised with C4H8OH pendants, which are suitable for further modifications and investigations. The reported methodology afforded in all cases products in their pure form, which were fully characterized by 1H NMR, 13C NMR, 2D COSY, HSQC, HMBC and DOSY techniques.