Supramolecular Assembly‐Induced Emission Enhancement Vesicles Regulated by Pincer‐Like Hosts Containing Pillar[5]arenes

Abstract

In 2001, Tang et al. reported luminescent organic molecules with aggregation-induced emission (AIE) feature, termed as AIEgen, which exhibiting intensive fluorescence emission in aggregated fashion compared with those in good solvent, providing new strategy to overcome the notorious ACQ effect. [7][8][9] With the 20 years continuous development in AIE, researchers decipher AIE phenomenon by the restriction of intramolecular motions (RIM) rules containing both restriction of intramolecular rotations (RIR) and restriction of intramolecular vibrations (RIV). [10,11] Moreover, in order to fabricate fluorescence materials response to external/internal stimuli, combining AIEgen with supramolecular interactions, such as hydrogen bonding, [12][13][14][15] metal-coordination interactions, [16][17][18][19] π-π stacking interactions, [20][21][22] host-guest interactions, [23][24][25] electrostatic interactions, [26] hydrophobic interactions, [27,28] etc., has proved to be a robust and significant strategy.Macrocyclic hosts involving cyclodextrins, cucurbiturils, crown ethers, calixarenes, and pillararenes are the most popular building blocks for the fabricating of supramolecular fluorescent materials with enhanced emission intensity, uniform morphology, fascinating chemical/physical properties, diverse stimuli-responsive properties, and environment adaptation. [29][30][31][32][33][34][35][36][37] The introduction of host-guest interactions based on pillararenes for the fabrication of supramolecular assemblyinduced emission enhancement (SAIEE) systems are regard as a crucial approach to fabricate supramolecular AIE systems, which was first demonstrated by Yang and co-workers in 2014. [38] In particular, pillar[5]arenes reported by Ogoshi et al. in 2008 was regard as a typical type of macrocycles in the construction of supramolecular luminescent materials due to their a) high binding affinity toward electron-deficient group in organic/ aqueous solution; b) high synthetic yield and simple process for further functionalization; c) symmetrical rigid column structure. [39][40][41][42] For instance, the emission intensity of supramolecular polymer networks constructed by tetraphenylethene Supramolecular assembly-induced emission enhancement (SAIEE) systems have been proved to be a highly efficient approach for the fabrication of luminescent nanoparticles with uniform morphology. Herein, fluorescent supramolecular vesicles are constructed from tetraphenylethene-based cyano-alkane tetramer (TPE-(CN) 4 ) and pincer-like hosts containing two pillar[5]arene units (B-(TAP[5]A) 2 ) through a synergistic effect of host-guest interactions and hydrophobic interactions. Notably, the emission intensity of supramolecular vesicles can be remarkably enhanced with quantum yield determined to be 37.69%, whereas that of TPE-(CN) 4 is only 18.93% in mixture solvent. Furthermore, the supramolecular vesicles can retard the photocyclization reaction of TPE-(CN) 4 under UV light and exhibit considerable emission intensity at high temperature. Enthused ...

Ordered nanoassemblies from self‐assembly of amphiphilic molecule containing pillar[5]arene and azobenzene groups

“…According to previous reports, the fluorescence intensity of tetraphenylethylene derivatives similar to G 1 would be greatly enhanced under the bonding of host-guest interaction. 53 While, in this system, with the addition of the host H 1 in chloroform solution of G 1 , the tendency of fluorescence quenching appears (Fig. 4 (b)).…”

Application of Nanomaterials in the Production of Biomolecules in Microalgae: A Review

“…The design and synthesis of ideal scaffolds are complex. To greatly simplify the fabrication steps of special scaffolds, the employment of AIE materials was presented [69,70]. In addition, supramolecular polymerization is an excellent strategy for constructing light-harvesting NMs, which can assemble the chromophores together to pack tightly and enhance supramolecular assembly-induced emission of the chromophores [70].…”

A luminescent supramolecular polymer based on a stiff-stilbene bridged pillar[5]arene as a Pd2+-responsive smart material

“…30 Inspired by that, many efforts have been devoted to the design and preparation of functionalized P[5]s over the past two decades. 31 It is well-known that bridged P[5] dimers, 32 trimers 33 or tetramers 34 are another rising star in the field of supramolecular functional materials 35 because they can form stable complexes with guests through intramolecular cooperative binding. However, the challenges in their tedious preparation make bridged P[5]s rarely reported and applied in supramolecular polymers.…”