A Dynamic and Responsive Host in Action: Light‐Controlled Molecular Encapsulation

Abstract

The rational design of af lexible molecular box, oAzoBox 4+,incoporating both photochromic and supramolecular recognition motifs is described. We exploit the E$Z photoisomerization properties of azobenzenes to alter the shape of the cavity of the macrocycle upon absorption of light. Imidazolium motifs are used as hydrogen-bonding donor components,a llowing for sequestration of small molecule guests in acetonitrile.U pon E!Zp hotoisomerization of oAzoBox 4+ the guest is expelled from the macrocyclic cavity.

Topologically Controlled Synthesis of Reversible Macrocyclic Compounds in Microemulsions

“…23 In their study, the olefinic bonds on the terminals of poly(ethylene glycol) derivatives were exploited to synthesis photoreversible cyclobutanocrown ethers in methanol by UV light. However, other examples of responsive macrocyclic compounds are limited 21,24 and, to our knowledge, there is no report showing the synthesis of photoreversible opening and closing of macrocyclic compounds from two separated molecules.…”

Cucurbit[7]uril-Directed Assembly of Colloidal Membrane and Stimuli-Responsive Microcapsules at the liquid–liquid Interface

“…There- fore, it has been challenging to increase the molecular diversity into an assembly and expand the scope of these supramolecular assemblies by integrating a variety of attractive host−guest systems that lack these abilities. A prime example of this class of host system is cucurbit [7]uril (CB [7]). 28−33 Albeit being one of the most well-known and attractive host system, it has never been featured in the interfacial NP assembly because of its inability to incorporate multiple guests and difficulty in functional modification.…”

“…The utility and potential of the supramolecularly assembled systems encouraged us to search for a novel assembling mechanism that is simple, possess unique features, and can increase material diversity in the resultant assemblies by integrating new molecules from the available repertoire of host−guest systems. 34−42 In this article, we report a new supramolecular strategy for the NP assembly that relies on interfacial host−guest molecular recognition between aminohexyl-terminated gold NPs (Hex-AuNPs) and complementary CB [7] molecule. In contrast to the traditionally used crosslinking approach, our current strategy exploits the engineered interaction between organic soluble Hex-AuNPs and water soluble CB [7] host to tune the interfacial energy and stabilize the NP assembly at the liquid−liquid interface (Scheme 1).…”

“…Herein, we report a new strategy to fabricate the colloidal membrane and stimuli-responsive microcapsules by utilizing cucurbit[7]uril-mediated interfacial host−guest molecular recognition. In contrast to the traditionally used crosslinking approach, this method exploits the engineered interaction between a nanoparticle ligand and cucurbit [7]uril to tune the interfacial energy and stabilize the colloidal assembly at the interface. These capsules provide a versatile platform for simultaneous encapsulation of dual cargos.…”

Highly efficient synthesis of non-planar macrocycles possessing intriguing self-assembling behaviors and ethene/ethyne capture properties

“…Design and synthesis of macrocycles featuring characteristic host-guest properties and self-assembling behaviors are always one of the cutting-edge research topics in the supramolecular chemistry [1][2][3][4][5] . The development of macrocyclic host-guest system is not only very conducive to exploring, explaining and understanding the non-covalent interactions but also endows the macrocycles with more recognition functions [6][7][8][9][10][11][12][13][14][15][16][17][18] . Meanwhile, the self-assembly of macrocycles into higher-order nanostructures such as columns and channels has found wide applications in the fields of supramolecular delivery systems and porous materials [19][20][21] .…”