We have designed and synthesized two amphiphilic calix[6]arene derivatives, CA8 and CA18, that combine the potential to act as wheel components for pseudorotaxane structures with the self-assembly features typical of surfactant molecules in aqueous solution. Their endo-cavity recognition and self-aggregation properties were compared with those of a non-amphiphilic analogue, C8. TEM, DLS, and fluorescence experiments show that in water the amphiphilic calixarenes form vesicle- and micelle-like aggregates. The size, nature and properties of such aggregates depend on the length of the alkyl chain anchored at the lower rim of the calix[6]arene skeleton, as well as on the inclusion of a molecular guest into the wheel. Specifically, the release of a fluorescent guest entrapped inside the CA8 vesicles is accelerated in the presence of dioctylviologen axles that can pierce the calixarene cavity.
Hierarchical self-assembly of amphiphilic calix[6]arene wheels and viologen axles in water / Rocco Bussolati; Pasquale Carrieri; Andrea Secchi; Arturo Arduini; Alberto Credi; Monica Semeraro; Margherita Venturi; Serena Silvi; Diana Velluto; Romina Zappacosta; Antonella Fontana. - In: ORGANIC & BIOMOLECULAR CHEMISTRY. - ISSN 1477-0520. - STAMPA. - 11:(2013), pp. 5944-5953. [10.1039/c3ob40739j]
Hierarchical self-assembly of amphiphilic calix[6]arene wheels and viologen axles in water
CREDI, ALBERTO;SEMERARO, MONICA;VENTURI, MARGHERITA;SILVI, SERENA;
2013
Abstract
We have designed and synthesized two amphiphilic calix[6]arene derivatives, CA8 and CA18, that combine the potential to act as wheel components for pseudorotaxane structures with the self-assembly features typical of surfactant molecules in aqueous solution. Their endo-cavity recognition and self-aggregation properties were compared with those of a non-amphiphilic analogue, C8. TEM, DLS, and fluorescence experiments show that in water the amphiphilic calixarenes form vesicle- and micelle-like aggregates. The size, nature and properties of such aggregates depend on the length of the alkyl chain anchored at the lower rim of the calix[6]arene skeleton, as well as on the inclusion of a molecular guest into the wheel. Specifically, the release of a fluorescent guest entrapped inside the CA8 vesicles is accelerated in the presence of dioctylviologen axles that can pierce the calixarene cavity.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.