Developing a new strategy to improve the self‐assembly efficiency of functional assemblies in a confined space and construct hybrid functional materials is a significant and fascinating endeavor. ...Herein, we present a highly efficient strategy for achieving the supramolecular self‐assembly of well‐defined metallacages in microdroplets through continuous‐flow microfluidic devices. The high efficiency and versatility of this approach are demonstrated by the generation of five representative metallacages in different solvents containing water, DMF, acetonitrile, and methanol in a few minutes with nearly quantitative yields, in contrast to the yields obtained with the hour‐scale reaction time in a batch reactor. A ring‐opening catalytic reaction of the metallacages was selected as a model reaction for exploring supramolecular catalysis in microdroplets, whereby the catalytic yield was enhanced by 2.22‐fold compared to that of the same reaction in the batch reactor. This work illustrates a new promising approach for the self‐assembly of supramolecular systems.
Supramolecular self‐assembly of well‐defined metallacages in microdroplets was achieved through a continuous‐flow microfluidic approach. The high efficiency and diversity of this strategy were illustrated by the generation of five representative metallacages with nearly quantitative yields in a few minutes. This approach is promising for the self‐assembly of supramolecular systems in a confined space.
Display omitted
•The synthetic strategies of supramolecular hexagonal metallacycles are reviewed.•Supramolecular hexagonal metallacycles in equilibrium and transformation are ...discussed.•Functionalized supramolecular hexagonal metallacycles are summarized.•Application of supramolecular hexagonal metallacycles are presented.
The formation and growth of natural objects are affected by the available space and materials. A regular hexagon is one of three regular polygons that can overlap without a plane. Among these three regular polygons (equilateral triangle, regular quadrilateral, and regular hexagon), the regular hexagon occupies the largest area with the smallest amount of material. The construction of supramolecular hexagonal architectures has been of great interest within supramolecular chemistry and materials science. Since supramolecular self-assembly enables the preparation of highly complex supramolecular systems from relatively simple building blocks, various metallosupramolecular hexagonal architectures have been successfully constructed under mild conditions by employing facile coordination-driven self-assembly strategy, and some of the architectures have exhibited wide ranges of applications in the fields of catalysis, electrochemistry, photochemistry, molecular sensing, etc. This review summarizes recent advances in the field of supramolecular hexagonal metallacycles. The design, self-assembly, and applications of various supramolecular hexagonal metallacycles, especially those incorporating functional moieties, will be discussed.
Over the past few years, the fabrication of artificial light‐harvesting systems with aggregation‐induced emission (AIE) has attracted significant attention because of the wide applications of these ...systems in organic chemistry, supramolecular chemistry, energy chemistry, and even materials science. This progress report focuses on recent advances in the design and preparation of artificial light‐harvesting systems with AIE. In addition, the properties, functions, and applications of these systems are discussed.
Recent progress in the fabrication of supramolecular artificial light‐harvesting systems with aggregation‐induced emission is reviewed, with an emphasis on their preparation, properties, functions, and applications. The future challenges and potential research opportunities are also discussed. Such artificial light‐harvesting systems will attract increasing attention and play an important role in supramolecular chemistry, energy chemistry, and materials science over the next decades.
Coordination-driven self-assembly has emerged as a powerful bottom-up approach to construct various supramolecular architectures with increasing complexity and functionality. Tetraphenylethylene ...(TPE) has been incorporated into metallo-supramolecules to build luminescent materials based on aggregation-induced emission. We herein report three generations of ligands with full conjugation of TPE with 2,2':6',2″-terpyridine (TPY) to construct emissive materials. Due to the bulky size of TPY substituents, the intramolecular rotations of ligands are partially restricted even in dilute solution, thus leading to emission in both solution and aggregation states. Furthermore, TPE-TPY ligands are assembled with Cd(II) to introduce additional restriction of intramolecular rotation and immobilize fluorophores into rosette-like metallo-supramolecules ranging from generation 1-3 (G1-G3). More importantly, the fluorescent behavior of TPE-TPY ligands is preserved in these rosettes, which display tunable emissive properties with respect to different generations, particularly, pure white-light emission for G2.
Lithium‐metal (Li) electrode has been regarded as an excellent option to increase the energy density of next‐generation secondary batteries due to its low electrochemical potential and ultrahigh ...theoretical capacity. However, Li electrodes suffer from poor Coulombic efficiency (CE) and uneven lithium deposition issues during cycling that severely restrain its application. Herein, ammonium perfluoro(2‐methyl‐3‐oxahexanoate) (APFA), a pragmatic anionic surfactant, is introduced as an electrolyte additive to regulate the deposition behavior of lithium. Different from the conventional sacrificial additives that reinforce solid electrolyte interphase (SEI) layers on Li electrodes, the PFA− anions are mainly adsorbed on the Li surface, which improves the electron transfer step kinetics due to the ψ1 effect. The introduction of APFA in the electrolyte promises homogeneous and highly dense lithium deposition and the LiLi symmetric cell with APFA can operate over 4000 h with excellent stability and low polarization. This work provides a facile and promising strategy for fabricating stable Li anode for high‐energy‐density secondary batteries.
An organic surfactant of ammonium perfluoro(2‐methyl‐3‐oxahexanoate) as an electrolyte additive is employed for lithium electrodes. Because of the adsorption of the additive anions and the adapted electrical double layer on the surface, the electrode kinetics is greatly promoted, thus enabling a stable lithium electrode.
The development of optical imaging techniques has led to significant advancements in single‐nanoparticle tracking and analysis, but these techniques are incapable of label‐free selective nanoparticle ...recognition. A label‐free plasmonic imaging technology that is able to identify different kinds of nanoparticles in water is now presented. It quantifies the plasmonic interferometric scattering patterns of nanoparticles and establishes relationships among the refractive index, particle size, and pattern both numerically and experimentally. Using this approach, metallic and metallic oxide particles with different radii were distinguished without any calibration. The ability to optically identify and size different kinds of nanoparticles can provide a promising platform for investigating nanoparticles in complex environments to facilitate nanoscience studies, such as single‐nanoparticle catalysis and nanoparticle‐based drug delivery.
Easy identification: Nanoparticles with different compositions and radii were identified by precisely quantifying the plasmonic interferometric scattering patterns of nanoparticles. This technique can be used to investigate nanoparticles in a complex environment.
Expanded azahelicenes, as heteroanalogues of helically chiral helicenes, hold significant potential for chiroptical materials. Nevertheless, their investigation and research have remained largely ...unexplored. Herein, we present the facile synthesis of a series of expanded azahelicenes NHn (n=1–5) consisting of 11, 19, 27, 35, and 43 fused rings, mainly by Suzuki coupling followed by Bi(OTf)3‐mediated cyclization of vinyl ethers. The structures of NH2, NH3 and NH4 were confirmed through X‐ray crystallography analysis, and their (P)‐ and (M)‐ enantiomers were also isolated with chiral high performance liquid chromatography. The enantiomers exhibit large absorption (abs) and luminescence (lum) dissymmetry factors, with |gabs|max=0.044; |glum|max=0.003 for NH2, |gabs|max=0.048; |glum|=0.014 for NH3, and |gabs|max=0.043; |glum|max=0.021 for NH4, which are superior to their respective all‐carbon analogues.
Expanded azahelicenes consisting of up to 43 rings are accessible by a facile synthesis. The enantiomers of the acquired azahelicenes exhibited large dissymmetry factors with up to 0.048 (gabs) and 0.021 (glum), respectively.
In the past few years, a new family of supramolecular metallodendrimers, which possess cavities with well-defined shape and size, have attracted widespread attention. Coordination-driven ...self-assembly has proven to be a simple and highly efficient approach for the preparation of cavity-cored supramolecular metallodendrimers. This
feature article
focuses on the recent progress in the construction of a variety of cavity-cored supramolecular metallodendrimers
via
coordination-driven self-assembly. The characterization and hierarchical self-assembly behaviour of such metallodendrimers are also discussed.
This
feature article
reviews the recent progress in the construction of cavity-cored supramolecular metallodendrimers
via
coordination-driven self-assembly.
Conspectus During recent decades, the blossoming of the field of mechanically interlocked molecules (MIMs), i.e., molecules containing mechanical or topological bonds such as rotaxanes, catenanes, ...and knots, has been reported in the literature. Taking advantage of the rapid development of diverse synthetic strategies, the precise control of both the architectures and topologies of MIMs has become realizable, which thus enables the construction of MIMs with specially desired functions. By mimicking biomolecular machines, a variety of MIM-based artificial molecular machines such as molecular shuttles, molecular muscles, molecular motors, and molecular assemblers have been constructed and operated by relying on the unique interlocked structures and controllable intramolecular movements. Two pioneers in this field, J. Fraser Stoddart and Jean-Pierre Sauvage, were awarded the 2016 Nobel Prize in Chemistry, thereby marking a golden age of MIMs. Along with the burgeoning of MIMs, the engineering of mechanical bonds into macromolecular scaffolds such as polymers or dendrimers has become an attractive topic since the targeted novel mechanically bonded macromolecules would feature interesting processable and mechanical properties, making them excellent candidates for practical applications such as device fabrication or smart materials. In particular, rotaxane dendrimers, attributed to the combination of the advantageous features of both rotaxanes (controllable dynamic motions) and dendrimers (nanoscale highly branched architectures), have evolved as versatile platforms for extensive applications such as gene delivery, light harvesting, and molecular nanoreactors. However, compared with the widely investigated polyrotaxanes and polycatenanes, in-depth investigations on rotaxane dendrimers have rarely been explored mainly because of the synthetic challenge that makes the preparation of diverse rotaxane dendrimers, especially high-generation ones, extremely difficult. During recent years, through the rational design and synthesis of organometallic rotaxane units as key building blocks, the employment of a controllable divergent approach led to the successful synthesis of a variety of rotaxane dendrimers with precise arrangements of rotaxane units as well as stimuli-responsive sites and functional groups. More importantly, on the basis of the synthetic accessibility to diverse rotaxane dendrimers, rotaxane dendrimers have been proven to hold great promise for extensive applications in diverse fields such as light harvesting, photocatalysis, and soft actuators. In this Account, we summarize our expedition in rotaxane dendrimers, including addressing the synthetic challenges, investigating their stimuli-responsive properties, expanding their potential applications, and inventing higher-order daisy chain dendrimers. We believe that this Account will inspire scientists from various disciplines to explore these appealing and versatile higher-order mechanically bonded macromolecules.
Aberrant microRNAs are widely identified in multiple cancers, including lung cancer. miR‐135a‐5p can function as a significant tumor regulator in diverse cancers via impacting multiple genes in ...oncogenic pathways. Nevertheless, the biological role of miR‐135a‐5p in lung cancer is poorly known. Here, we investigated its function in lung cancer. As exhibited, miR‐135a‐5p was elevated in lung cancer cells in contrast to BEAS‐2B cells. Then, we inhibited miR‐135a‐5p expression by transfecting LV‐anti‐miR‐135a‐5p into lung cancer cells. As displayed, miR‐135a‐5p was obviously reduced in A549 and H1299 cells. Knockdown of miR‐135a‐5p repressed lung cancer cell growth and cell proliferation. Meanwhile, cell colony formation capacity was depressed, cell apoptosis was enhanced and cell cycle progression was blocked in G1 phase by inhibition of miR‐135a‐5p in vitro. Additionally, the migration and invasion of A549 and H1299 cells was strongly depressed by LV‐anti‐miR‐135a‐5p. For another, by using informatics analysis, lysyl oxidase‐like 4 (LOXL4) was speculated as the downstream target of miR‐135a‐5p. We validated their direct correlation and moreover, overexpression of miR‐135a‐5p restrained LOXL4 levels in lung cancer cells. Subsequently, we proved that miR‐135a‐5p promoted lung cancer development via targeting LOXL4 by carrying out the in vivo assays. Taken these together, our study revealed miR‐135a‐5p might be indicated as a perspective for lung cancer via targeting LOXL4.
We found that lysyl oxidase‐like 4 (LOXL4) was decreased in lung cancer cells, and LOXL4 was a target of miR‐193a‐3p. Meanwhile, miR‐135a‐5p might promote lung cancer progression via repressing LOXL4. We reported miR‐135a‐5p exhibited an oncogenic role in lung cancer via regulating LOXL4 and miR‐135a‐5p acted as a significant biomarker for lung cancer progression.
PDF
