The development of new strategies to construct on-demand porous lattice frameworks from simple motifs is desirable. However, mitigating complexity while combing multiplicity and reversibility in the ...porous architectures is a challenging task. Herein, based on the synergy of dynamic intermolecular interactions and flexible molecular conformation of a simple cyano-modified tetraphenylethylene tecton, eleven kinetic-stable hydrogen-bonded organic frameworks (HOFs) with various shapes and two thermo-stable non-porous structures with rare perpendicular conformation are obtained. Multimode reversible structural transformations along with visible fluorescence output between porous and non-porous or between different porous forms is realized under different external stimuli. Furthermore, the collaborative of flexible framework and soft long-chain guests facilitate the relaxation from intrinsic blue emission to yellow emission in the excited state, which represents a strategy for generating white-light emission. The dynamic intermolecular interactions, facilitated by flexible molecular conformation and soft guests, diversifies the strategies of construction of versatile smart molecular frameworks.
Supramolecular macrocyclic hosts have long been used in smart materials. However, their triplet emission and regulation at crystal level is rarely studied. Herein, ultralong and universal ...room‐temperature phosphorescence (RTP) is reported for traditional crown ethers. A supramolecular strategy involving chain length adjustment and morphological locking through complexation with K+ was explored as a general method to tune the phosphorescence lifetime in the solid state. A maximum 10‐fold increase of lifetime after complex formation accompanied with by invisible to visible phosphorescence was achieved. A deep encryption based on this activated RTP strategy was also facilely fabricated. This work thus opens a new world for supramolecular macrocycles and their intrinsic guest responsiveness offers a new avenue for versatile smart luminescent materials.
Traditional crown ether is injected with fresh blood of room‐temperature phosphorescence in crystalline state. Supramolecular interactions introduced by multiple oxygen atoms and K+ were explored as a general method to tune lifetime. This work opens a new world for crown ether and its intrinsic guest responsiveness offers a new avenue for versatile smart luminescent materials.
We prepared a poly3rotaxane consisting of a ''topologically linked polymer backbone'' in one pot from readily available, modular building blocks via a dynamic polymerization strategy based on ...reversible anthracene dimerization.
Cyanide is extremely hazardous to living organisms and the environment. Owing to its wide range of applications and high toxicity, the development of functional materials for cyanide detection and ...sensing is highly desirable. Host–guest complexation between bis(p‐phenylene)‐34‐crown‐10 H and N‐methylacridinium salt G remarkably decreases the detection limit for cyanide anions compared with that of the guest itself. The 2pseudorotaxane selectively recognizes the cyanide anion with high optical sensitivity as a result of the nucleophilic addition of the cyanide anion at the 9‐position of G. The host–guest complexation is further incorporated into supramolecular materials for the visual detection of cyanide anions, especially the detection of cellular cyanide excretion with a detection limit of 0.6 μm. This supramolecular method provides an extremely distinct strategy for the visual detection of cyanide anions.
Detecting cyanide: Host–guest complexation between bis(p‐phenylene)‐34‐crown‐10 and N‐methylacridinium salt is studied in both solution and the solid state. This host–guest complexation is responsive to CN−. The 2pseudorotaxane is used in the visual detection of cellular cyanide anion excretion with a detection limit of 0.6 μm.
Host–guest complexation between an alkane functionalized with triazole moieties and three pillar5arenes was studied. Three pillar5arene-based 2rotaxanes were constructed based on this new recognition ...motif. The sequence of the yields of these 2rotaxanes was consistent with the order of association constants between the three corresponding pillar5arenes and the alkane. 1H NMR, electrospray ionization mass spectrometry, and NOESY NMR were employed to characterize these 2rotaxanes.
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Herein we report a linear ionic molecule that assembles into a supramolecular nano‐tunnel structure through synergy of trident‐type ionic interactions and π–π stacking interactions. The nano‐tunnel ...crystal exhibits anisotropic guest adsorption behavior. The material shows good thermal stability and undergoes multi‐stage single‐crystal‐to‐single‐crystal phase transformations to a nonporous structure on heating. The material exhibits a remarkable chemical stability under both acidic and basic conditions, which is rarely observed in supramolecular organic frameworks and is often related to structures with designed hydrogen‐bonding interactions. Because of the high polarity of the tunnels, this molecular crystal also shows a large CO2‐adsorption capacity while excluding other gases at ambient temperature, leading to high CO2/CH4 selectivity. Aggregation‐induced emission of the molecules gives the bulk crystals vapochromic properties.
A linear ionic molecule forms a stable framework with open pores through X‐aggregation packing, facilitated by a combination of trident‐type ionic interactions and π–π stacking. The nano‐tunnel exhibits anisotropic guest diffusion, excellent chemical stability, large CO2 uptake with high CO2/CH4 selectivity, and vapochrometric behavior.
Efficient host–guest complexation and interesting self‐assembled structures formed between two crown ether‐based cryptands and a 1,2‐bis(4‐pyridinium)ethane derivative 3 are reported. By ...self‐assembly of cis‐dibenzo‐24‐crown‐8‐based cryptand 1 and guest 3, a 3pseudorotaxane was formed in solution, which further formed a supramolecular poly3pseudorotaxane structure in the solid state driven by π‐π stacking interactions. Meanwhile, a 2pseudorotaxane, obtained from self‐assembly of a bis(m‐phenylene)‐32‐crown‐10‐based cryptand 2 and guest 3, can form a supramolecular poly2pseudorotaxane structure in the solid state. This difference in the binding model reflects the diversity of host–guest chemistry of crown ether‐based cryptands. Furthermore, these host–guest recognition processes and self‐assembled structures were fully characterized by 1H NMR, UV/Vis spectroscopy, electrospray ionization mass spectrometry, and single‐crystal X‐ray analysis. Interestingly, formation of the 3pseudorotaxane between cryptand 1 and guest 3 can be reversibly controlled by adding and removing potassium cations in acetone. This reversible complexation process provides a simple on/off mechanism that can be used in the construction of controllable molecular switches.
Host–guest complexation and self‐assembled structures formed between two crown ether‐based cryptands and a 1,2‐bis(4‐pyridinium)ethane derivative are reported. A 3pseudorotaxane forms from a dibenzo‐24‐crown‐8‐based cryptand and the 1,2‐bis(4‐pyridinium)ethane derivative, whereas a 2pseudorotaxane is obtained from a bis(m‐phenylene)‐32‐crown‐10‐based cryptand and the same guest.
Kasha's rule, which states that all exciton emissions occur from the lowest excited state and are independent of excitation energy, makes high‐energy excitons difficult to use and severely hinders ...the widespread applications of organic photoluminescent materials in the real world. For decades, scientists have tried to break this rule to unleash the power of high‐energy excitons, but only minimal progress has been achieved, with no rational guiding principles provided, and few applications developed. So far, breaking Kasha's rule has remained a purely academic concept. In this paper, we introduce a design principle for a purely organic anti‐Kasha system and synthesise a series of compounds based on the design rule. As predicted, these compounds all display evident S2 emissions in dilute solutions. In addition, we introduce a highly accurate (over 90%) convolutional neural network as an assistant for the classification of cells using anti‐Kasha luminogens, thereby providing a new application direction for anti‐Kasha systems.
This paper provided a paradigm of an integrated chain to realize, design, synthesize, analyze, tune and utilize a system with anti‐Kasha behavior. Anti‐Kasha system in this work displayed not only academic and theoretical uniqueness, but also usefulness in cell‐imaging with high contrast. Our work will make the anti‐Kasha system more practical than theoretical, to unleash the power of infinite excited states.
A novel diblock copolymer with a hydrophobic supramolecular polymer block and a hydrophilic traditional polymer block has been prepared. Control over the chain length ratio of the two blocks is ...obtained by simply changing the concentration proportion of the monomer of the supramolecular polymer block to the traditional polymer block in solution. When the chain length ratio of the two blocks is changed, the formation of various self‐assembly morphologies is achieved.
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![[2]Pseudorotaxane‐Based Sup...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/0947-6539/small "[2]Pseudorotaxane‐Based Supramolecular Optical Indicator for the Visual Detection of Cellular Cyanide Excretion")
![Novel [2]rotaxanes based on...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/0040-4020/small "Novel [2]rotaxanes based on the recognition of pillar[5]arenes to an alkane functionalized with triazole moieties")
![[n]Pseudorotaxanes (n = 2, ...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1434-193X/small "[n]Pseudorotaxanes (n = 2, 3) from Self-Assembly of Two Cryptands and a 1,2-Bis(4-pyridinium)ethane Derivative")
