Assembling features of calixarene-based amphiphiles and supra-amphiphiles
Macrocyclic amphiphiles as an emerging family of artificial amphiphiles have gained considerable attention in recent years on account of their fascinating recognition and assembly properties. Benefiting from preorganized framework, facile modification and host-guest recognition ability, calixarenes have been widely used to fabricate self-assemblies of both amphiphiles and supra-amphiphiles. In this review, we organized hundreds of reported amphiphilic calixarenes based on their structures and systematically summarized assembling features of calixarene-based amphiphiles and supra-amphiphiles. For amphiphilic calixarenes, the size and conformation of skeletons significantly affect their assembly behaviors, such as lower critical aggregation concentration (CAC) and more diverse morphology than conventional amphiphiles. Besides, we also focus on the emerging topic like uniformity, compactness, and kinetics property of calixarene aggregation. For supra-amphiphiles, the binding affinities of calixarenes enable them the ability of inducing guest assembly. On the contrary, complexation of guests also improve an amphiphilic calixarene aggregation. Obtained assemblies not only possess the advantages of low CAC and compact packing, but also respond to various stimuli. Finally, we pointed several research topics of calixarene-based amphiphiles and supra-amphiphiles to be further developed in the future, such as the relationship between molecular structures and assembling properties, crosslink, co-assembly, and utilization of cavity. We hope this review could be a guidance for studying amphiphilic assembly based on calixarenes and other macrocyclic compounds.
- This article is part of the themed collection: Supra-amphiphiles