Solvent‐tuned supramolecular assembly of fluorescent catechol/pyrene amphiphilic molecules

Nador, F.; Wnuk, K.; Roscini, C.; Solorzano, R.; Faraudo, J.; Ruiz-Molina, D.; Novio, F.

Chemistry - A European Journal, , , (2018)
DOI: 10.1002/chem.201802249

Abstract: The synthesis and structuration of a novel low molecular amphiphilic catechol 1 is reported. The combination of a hydrophilic tail containing a catechol group and a pyrene‐based hydrophobic head favors its solvent tuned supramolecular assembly. Formation of hollow nanocapsules/vesicles occurs in concentrated solutions of both polar protic and non‐protic organic solvents, whereas in water a fibril‐like aggregation process is favored even at low concentrations. The emission properties of the pyrene moiety have allowed the monitoring of the self‐assembly process which could be confirmed by optical and electronic microscopy. In organic solvents and at low concentrations, compound 1 remains on its non‐assembled monomeric form. As the concentration increases, the aggregation containing pre‐associated pyrene moieties becomes more evident up to a critical micellar concentration where vesicle‐like structures are formed. In contrast, nanosized twist belt‐like fibers have been observed in water even at low concentrations, meanwhile at high concentration microplate structures appears. The interactions between molecules in different solvents have been studied by molecular dynamics simulations, which have confirmed different solvent driven supramolecular interactions.

Solvent‐tuned supramolecular assembly of fluorescent catechol/pyrene amphiphilic molecules
Fluorescent catechol-based hollow nanocapsules/vesicles