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Metallo‐supramolecular cages have garnered tremendous attention for their diverse yet molecular‐level precision structures. However, the physical properties of these supramolecular ensembles, which are of potential significance in molecular electronics, remain largely unexplored. We herein constructed a series of octahedral metallo‐cages and cage‐fullerene complexes with notably enhanced structural stability. As such, we could systematically evaluate the electrical conductivity of these ensembles at both the single‐molecule level and aggregated bulk state (as well‐defined films). Our findings reveal that counteranions and fullerene guests play a pivotal role in determining the electrical conductivity of the aggregated state, while such effects are less significant for single‐molecule conductance. Both the counteranions and fullerenes effectively tune the electronic structures and packing density of metallo‐supramolecular assemblies, and facilitate efficient charge transfer between the cage hosts and fullerenes, resulting in a notable one order of magnitude increase in the electrical conductivity of the aggregated state. [ABSTRACT FROM AUTHOR]

Photodynamic therapy (PDT), as an emerging cancer treatment, requires the development of highly desirable photosensitizers (PSs) with integrated functional groups to achieve enhanced therapeutic efficacy. Coordination‐driven self‐assembly (CDSA) would provide an alternative approach for combining multiple PSs synergistically. Here, we demonstrate a simple yet powerful strategy of combining conventional chromophores (tetraphenylethylene, porphyrin, or Zn‐porphyrin) with pyridinium salt PSs together through condensation reactions, followed by CDSA to construct a series of novel metallo‐supramolecular PSs (S1–S3). The generation of reactive oxygen species (ROS) is dramatically enhanced by the direct combination of two different PSs, and further reinforced in the subsequent ensembles. Among all the ensembles, S2 with two porphyrin cores shows the highest ROS generation efficiency, specific interactions with lysosome, and strong emission for probing cells. Moreover, the cellular and living experiments confirm that S2 has excellent PDT efficacy, biocompatibility, and biosafety. As such, this study will enable the development of more efficient PSs with potential clinical applications. [ABSTRACT FROM AUTHOR]

Use of abiotic chemical systems for understanding higher order superstructures is challenging. Here we report a ring‐in‐ring(s) system comprising a hydrogen‐bonded macrocycle and cyclobis(paraquat‐o‐phenylene) tetracation (o‐Box) or cyclobis(paraquat‐p‐phenylene) tetracation (CBPQT4+, p‐Box) that assembles to construct discrete higher order structures with adaptive conformation. As indicated by mass spectrometry, computational modeling, NMR spectroscopy, and single‐crystal X‐ray diffraction analysis, this ring‐in‐ring(s) system features the box‐directed aggregation of multiple macrocycles, leading to generation of several stable species such as H4G (1 a/o‐Box) and H5G (1 a/o‐Box). Remarkably, a dimeric shish‐kebab‐like ring‐in‐rings superstructure H7G2 (1 a/o‐Box) or H8G2 (1 a/p‐Box) is formed from the coaxial stacking of two ring‐in‐rings units. The formation of such unique dimeric superstructures is attributed to the large π‐surface of this 2D planar macrocycle and the conformational variation of both host and guest. [ABSTRACT FROM AUTHOR]

We herein report the preparation of a series of hexaphenylbenzene (HPB)‐based deep blue‐emissive metallacages via multicomponent coordination‐driven self‐assembly. These metallacages feature prismatic structures with HPB derivatives as the faces and tetracarboxylic ligands as the pillars, as evidenced by NMR, mass spectrometry and X‐ray diffraction analysis. Light‐harvesting systems were further constructed by employing the metallacages as the donor and a naphthalimide derivative (NAP) as the acceptor, owing to their good spectral overlap. The judiciously chosen metallacage serves as the antenna, providing the suitable energy to excite the non‐emissive NAP, and thus resulting in bright emission for NAP in the solid state. This study provides a type of HPB‐based multicomponent emissive metallacage and explores their applications as energy donors to light up non‐emissive fluorophores in the solid state, which will advance the development of emissive metallacages as useful luminescent materials. [ABSTRACT FROM AUTHOR]

The construction of solid‐state fluorescent materials with high quantum yield and good processability is of vital importance in the preparation of organic light‐emitting devices. Herein, a series of tetraphenylethylene (TPE)‐based multicomponent emissive metallacages are prepared by the coordination‐driven self‐assembly of tetra‐(4‐pyridylphenyl)ethylene, cis‐Pt(PEt3)2(OTf)2 and tetracarboxylic ligands. These metallacages exhibit good emission both in solution and in the solid state because the coordination bonds and aggregation restrict the molecular motions of TPE synergistically, which suppresses the non‐radiative decay of these metallacages. Impressively, one of the metallacages achieves very high fluorescence quantum yield (ΦF=88.46 %) in the solid state, which is further used as the coatings of a blue LED bulb to achieve white‐light emission. The study not only provides a general method to the preparation of TPE‐based metallacages but also explores their applications as solid‐state fluorescent materials, which will promote the future design and applications of metallacages as useful emissive devices. [ABSTRACT FROM AUTHOR]

Supramolecular cages/vesicles in biology display sophisticated structures and functions by utilizing a few types of protein subunit quasi‐equivalently at distinct geometrical locations. However, synthetic supramolecular cages still lack comparable complexity to reach the high levels of functionality found in natural systems. Herein we report the self‐assembly of giant pentagonal supramolecular prisms (molecular weight >50 kDa) with tetratopic pyridinyl subunits serving different geometrical roles within the structures, and their packing into a novel superstructure with unexpected three‐fold rotational symmetry in a single two‐dimensional layer of crystalline state. The formation of these complicated structures is controlled by both the predetermined angles of the ligands and the mismatched structural tensions created from the multi‐layered geometry of the building blocks. Such a self‐assembly strategy is extensively used by viruses to increase the volume and complexity of capsids and would provide a new approach to construct highly sophisticated supramolecular architectures. [ABSTRACT FROM AUTHOR]

We report (bis)aniline 4 which contains a central viologen and its self-assembly with aldehyde 5 and Fe(OTf)2 to yield tetrahedron 6. Complexation of 4 with CB[7] in the form of CB[7]•4•2PF6 allows the preparation of assembly 7 which contains 1.95 mechanically interlocked CB[7] units. Assemblies 6 and 7 are hydrolytically unstable due to their imine linkages. Redesign of our system with water stable 2,2ʹ-bipyridine end groups was realised in the form of ligands 11 and 16. Self-assembly of 11 with Fe(NTf2)2 gave tetrahedral MOP 12. Isomeric ligand 16 underwent self-assembly with Fe(OTf)2 to give cube 17. Precomplexation of ligands 11 and 16 with CB[7] gave the acetonitrile soluble CB[7]•11•2PF6 and CB[7]•16•2PF6 complexes. Self-assembly of CB[7]•11•2PF6 with Fe(OTf)2 gave tetrahedron 13 which contains 1.8 mechanically interlocked CB[7] units. Self-assembly of CB[7]•16•2PF6 with Fe(OTf)2 gave cube 13 which contains 6.59 interlocked CB[7] units. [ABSTRACT FROM AUTHOR]

Theranostic agents, taking the advantages of both imaging and therapeutic functions, are anticipated to be key components in the development of personalized medicine in which the therapeutic response can be real‐time monitored. Herein, three metallacycles with pendent adamantane groups are prepared by coordination‐driven self‐assembly of PtII ligands with anticancer activities and tetraphenylethylene derivatives with emission. β‐Cyclodextrin, which shows good host–guest interactions with adamantane moieties, was added to form amphiphilic supramolecular nanoparticles with the aim to enhance the aqueous solubilities and bioactivities of these metallacycles. Moreover, when rhodamine‐modified β‐cyclodextrin was used as the carrier, the release of the metallacycles from the nanoparticles could be monitored in situ through the fluorescence changes owing to the efficient fluorescence resonance energy transfer from the metallacycles to rhodamine‐modified β‐cyclodextrin. In vitro and in vivo studies showed that these nanoparticles not only served as cell imaging contrast agents but also displayed improved anticancer activities, allowing them to serve as potential candidates for cancer theranostics. This study provides a simple and efficient method to prepare theranostic agents by hierarchical supramolecular self‐assembly, which will pave the way for image‐guided cancer therapy, targeted cancer therapy, and related biomedical fields. [ABSTRACT FROM AUTHOR]

The self‐assembly of highly stable zirconium(IV)‐based coordination cages with aggregation induced emission (AIE) molecular rotors for in vitro bio‐imaging is reported. The two coordination cages, NUS‐100 and NUS‐101, are assembled from the highly stable trinuclear zirconium vertices and two flexible carboxyl‐decorated tetraphenylethylene (TPE) spacers. Extensive experimental and theoretical results show that the emissive intensity of the coordination cages can be controlled by restricting the dynamics of AIE‐active molecular rotors though multiple external stimuli. Because the two coordination cages have excellent chemical stability in aqueous solutions (pH stability: 2–10) and impressive AIE characteristics contributed by the molecular rotors, they can be employed as novel biological fluorescent probes for in vitro live‐cell imaging. [ABSTRACT FROM AUTHOR]

Two rhomboidal metallacycles based on metal‐coordination‐driven self‐assembly are presented. Because metal‐coordination interactions restrict the rotation of phenyl groups on tetraphenylethene units, these metallacycles were emissive both in solution and in solid state, and their aggregation‐induced emission properties were well‐retained. Moreover, the rhomboidal metallacyclic structures offer a platform for intermolecular packing beneficial for the formation of liquid crystalline phases. Therefore, although neither of building blocks shows mesogenic properties, both thermotropic and lyotropic (in DMF) mesophases were observed in one of metallacycles, indicating that mesophases could be induced by metal‐coordination interactions. This study not only reveals the mechanism for the formation of cavity‐cored liquid crystals, but also provides a convenient approach to preparing supramolecular luminescent liquid crystals, which will serve as good candidates for chemo sensors and liquid crystal displays. [ABSTRACT FROM AUTHOR]

Peptide‐mediated self‐assembly is a prevalent method for creating highly ordered supramolecular architectures. Herein, we report the first example of orthogonal C−X⋅⋅⋅X−C/C−X⋅⋅⋅π halogen bonding and hydrogen bonding driven crystalline architectures based on synthetic helical peptides bearing hybrids of l‐sulfono‐γ‐AApeptides and natural amino acids. The combination of halogen bonding, intra‐/intermolecular hydrogen bonding, and intermolecular hydrophobic interactions enabled novel 3D supramolecular assembly. The orthogonal halogen bonding in the supramolecular architecture exerts a novel mechanism for the self‐assembly of synthetic peptide foldamers and gives new insights into molecular recognition, supramolecular design, and rational design of biomimetic structures. [ABSTRACT FROM AUTHOR]

Snowflake, a highly symmetrical hexagram figure, is challenging to be expressed by chemistry/supramolecular chemistry due to the complex structure. Herein, we have constructed super snowflake supramolecules using terpyridine (tpy)‐based metal‐organic building blocks with < tpy‐Ru(II)‐tpy> and < tpy‐Zn(II)‐tpy> connectivities through stepwise strategies in high yield. The structures were characterized by multi‐dimensional mass spectrometry and multi‐dimensional NMR spectrometry. In order to address the stability/tolerance of our designed super snowflake structures, ligand exchange behaviors between different supramolecules with various arm length were fully investigated by mass spectrometry. The study revealed that three modes could exist in such binary systems, including full exchange, partial exchange and self‐sorting (no exchange) depending on the length difference of ligands. [ABSTRACT FROM AUTHOR]

The double‐ or triple‐decker 3D metallo‐hexagons were obtained by self‐assembly of multitopic tris‐terpyridines with Cd2+ ions in near‐quantitative yield. Comprising up to 72 ionic pairs, the multiple spoked wheels display characteristic reversible gelation properties under thermodynamic conditions. The supramolecular metallo‐nanoarchitectures were characterized by 1H NMR, 2D NMR (COSY and NOESY), and diffusion‐ordered spectroscopy (DOSY) and HR‐ESI‐MS, traveling‐wave ion mobility mass spectrometry (TWIM‐MS), TEM, and AFM. For the first time, the self‐assembly of 45 units at once was demonstrated to yield exceptional giant triple‐decker hexagons of up to circa 42 000 Da. Big wheel keep on turning: Giant triple‐decker 3D metallohexagons were assembled from triple tris‐terpyridines and Cd2+ ions. Self‐assembly of 45 units at once yields exceptional metalloorganic hexagons with a molecular weight of circa 42 000 Da. Comprising up to 72 ion pairs, the molecular spoked wheels undergo characteristic reversible gelation under thermodynamic conditions. [ABSTRACT FROM AUTHOR]

Three generations of metalated trigonal supramolecular architectures, so-called metallo-triangles, were assembled from terpyridine (tpy) complexes. The first generation (G1) metallo-triangles were directly obtained by reacting a bis(terpyridinyl) ligand with a 60° bite angle and ZnII ions. The direct self-assembly of G2 and G3 triangles by mixing organic ligands and ZnII, however, only generated a mixture of G1 and G2, as well as a trace amount of insoluble polymer-like precipitate. Therefore, a modular strategy based on the connectivity of ⟨tpy−Ru2+−tpy⟩ was employed to construct two metallo-organic ligands for the assembly of G2 and G3 Sierpiński triangles. The metallo-organic ligands LA and LB with multiple free terpyridines were obtained through Suzuki cross-coupling of the RuII complexes, and then assembled with ZnII or CdII to obtain high-generation metallo-triangular architectures in nearly quantitative yield. The G1-G3 architectures were characterized by NOESY and DOSY NMR spectroscopy, ESI-MS, TWIM-MS, and transmission electron microscopy. [ABSTRACT FROM AUTHOR]

Two- and three-dimensional metallosupramolecules shaped like a Star of David were synthesized by the self-assembly of a tetratopic pyridyl ligand with a 180° diplatinum(II) motif and PdII ions, respectively. In contrast to other strategies, such as template-directed synthesis and stepwise self-assembly, this design enables the formation of 2D and 3D structures in one step and high yield. The structures were characterized by both one-dimensional (1H, 13C, 31P) and two-dimensional (COSY, NOESY, DOSY) NMR spectroscopy, ESI-MS, ion-mobility mass spectrometry (IM-MS), AFM, and TEM. The stabilities of the 2D and 3D structures were measured and compared by gradient tandem mass spectrometry (gMS2). The high stability of the 3D Star of David was correlated to its high density of coordination sites (DOCS). [ABSTRACT FROM AUTHOR]

A family of new alkynylplatinum(II) 2,6-bis(benzimidazol-2′-yl)pyridine (bzimpy)-functionalized supramolecular metallacycles with different shapes and sizes have been successfully prepared by coordination-driven self-assembly. The obtained metallacycles showed switchable emission and a strong tendency to form intermolecular Pt⋅⋅⋅Pt and π-π stacking interactions in solution that were not displayed by their individual precursors. Further investigation revealed that the existence of the metallacyclic scaffold at the core could facilitate the formation of intermolecular Pt⋅⋅⋅Pt and π-π stacking interactions of peripheral alkynylplatinum(II) bzimpy units. Moreover, the shapes and sizes of the metallacyclic scaffold have a significant influence on the hierarchical self-assembly behavior. Among the three metallacycles, hexagonal metallacycle A, with a relatively small size, could spontaneously self-assemble into an aromatic guest stimuli-responsive metallogel at room temperature without a heating-cooling process. [ABSTRACT FROM AUTHOR]

A new host molecule consists of four terpyridine groups as the binding sites with zinc(II) ion and a copillar[5]arene incorporated in the center as a spacer to interact with guest molecule was designed and synthesized. Due to the 120 ° angle of the rigid aromatic segment, a cross-linked dimeric hexagonal supramolecular polymer was therefore generated as the result of the orthogonal self-assembly of metal-ligand coordination and host-guest interaction. UV/Vis spectroscopy, 1H NMR spectroscopy, viscosity and dynamic light-scattering techniques were employed to characterize and understand the cross-linking process with the introduction of zinc(II) ion and guest molecule. More importantly, well-defined morphology of the self-assembled supramolecular structure can be tuned by altering the adding sequence of the two components, that is, the zinc(II) ion and the guest molecule. In addition, introduction of a competitive ligand suggested the dynamic nature of the supramolecular structure. [ABSTRACT FROM AUTHOR]

A new family of 120° carbazole-based dendritic donors D1- D3 have been successfully designed and synthesized, from which a series of novel supramolecular carbazole-based metallodendrimers with well-defined shapes and sizes were successfully prepared by [2+2] and [3+3] coordination-driven self-assembly. The structures of newly designed rhomboidal and hexagonal metallodendrimers were characterized by multinuclear NMR (1H and 31P) spectroscopy, ESI-TOF mass spectrometry, FTIR spectroscopy, and the PM6 semiempirical molecular orbital method. The fluorescence emission behavior of ligands D1- D3, rhomboidal metallodendrimers R1- R3, and hexagonal metallodendrimers H1- H3 in mixtures of dichloromethane and n-hexane with different n-hexane fractions were investigated. The results indicated that D1- D3 featured typical aggregation-induced emission (AIE) properties. However, different from ligands D1- D3, metallodendrimers R1- R3 and H1- H3 presented interesting generation-dependent AIE properties. Furthermore, evidence for the aggregation of these metallodendrimers was confirmed by a detailed investigation of dynamic light-scattering, Tyndall effect, and SEM. This research not only provides a highly efficient strategy for constructing carbazole-based dendrimers with well-defined shapes and sizes, but also presents a new family of carbazole-based dendritic ligands and rhomboidal and hexagonal metallodendrimers with interesting AIE properties. [ABSTRACT FROM AUTHOR]

The synthesis of discrete multirotaxanes with well-defined structures remains a great challenge. Herein, we present the successful construction of diverse discrete multirotaxanes with well-defined supramolecular metallacycles as cores by a modular approach. Moreover, these novel multirotaxanes featured a stimuli-responsive property that enabled the introduction and removal of the bromide anion by taking advantage of dynamic nature of the supramolecular metallacycle scaffold. Through the combination of rotaxane-containing prefunctionalized building blocks with the corresponding different organoplatinum(II) acceptor building blocks (60, 120, or 180°), diverse discrete multirotaxanes with well-defined metallacycles (rhomboid or hexagon) as cores as well as certain numbers of rotaxane units were successfully obtained quantitatively by means of coordination-driven self-assembly. Furthermore, owing to the existence of a dynamic metallacycle as the supramolecular cores, the resultant multirotaxanes showed anion-induced disassembly and reassembly properties, which allowed for the reversible transformation between multirotaxanes and the corresponding individual rotaxane-containing building blocks. Therefore, this research not only enriches the family of discrete multirotaxanes, but also provides a novel strategy for the construction of 'smart' stimuli-responsive multirotaxane systems. [ABSTRACT FROM AUTHOR]

A facile high yield, self-assembly process that leads to a terpyridine-based, three-dimensional, bis-rhomboidal-shaped, molecular wheel is reported. The desired coordination-driven supramolecular wheel involves eight structurally distorted tristerpyridine (tpy) ligands possessing a 60° angle between the adjacent tpy units and twelve Zn2+ ions. The tpy ligand plays dual roles in the self-assembly process: two are staggered at 180° to create the internal hub, while six produce the external rim. The wheel can be readily generated by mixing the tpy ligand and Zn2+ in a stoichiometric ratio of 2:3; full characterization is provided by ESI-MS, NMR spectroscopy, and TEM imaging. [ABSTRACT FROM AUTHOR]

Where there′s a wheel, there′s a way: The terpyridine‐based title system has been synthesized through a facile self‐assembly process. Two tris(terpyridine) ligands possessing angles of either 120° or 60° between adjacent tpy units were mixed with a stoichiometric amount of Zn2+ (2:6:12) to generate the desired coordination‐driven bicycle‐like wheel (90 % yield). [ABSTRACT FROM AUTHOR]

We report the self-assembly and isolation of two metallamacromolecular constitutional isomeric pairs based on connectivity. Utilizing a robust dimer with varying substitution to the core benzene ring resulted not only in the isolation of the expected 60°-oriented tetramer and 120°-oriented hexamer but also in the unexpected isolation of a 60°-oriented hexamer and a 120°-oriented tetramer. These isomers were characterized by 1H NMR spectroscopy and mass spectrometry (ESI-travelling wave ion mobility), which revealed significant structural differences. Molecular modeling was utilized to aid in characterization. [ABSTRACT FROM AUTHOR]

In this article, we report the facile synthesis, self-assembly, and characterization of shape amphiphiles (BPOSS-PDI-X) based on isobutyl-functionalized polyhedral oligomeric silsesquioxane (BPOSS), perylene tetracarboxylic diimide (PDI), and (60)fullerene (C60) moieties. Firstly, an asymmetrically functionalized diblock shape amphiphile precursor (BPOSS-PDI-OH) was obtained through the one-pot reaction between perylene-3,4,9,10-tetracarboxylic dianhydride and two different amines, namely BPOSS-NH2 and 3-amino-1-propanol. It was further conjugated with C60-COOH to give a tri-block shape amphiphile (BPOSS-PDI-C60). Their chemical structures were thoroughly characterized by NMR, IR and MALDI-TOF MS spectrometry. In order to gain insights on the structure-property relationship, their self-assembly in gas phase, in solution, and in solid state were characterized using traveling wave ion mobility mass spectrometry (TWIM-MS), UV/Vis absorption, fluorescence emission spectrophotometer, and transmission electron microscopy, respectively. It was found that BPOSS-PDI-OH formed more complicated dimers than BPOSS-PDI-C60. Both samples showed unique aggregation behaviors in solution with increasing concentration, which could be attributed neither to H- nor to J-type and might be related to the discrete dimers. While BPOSS-PDI-C60 could hardly crystalize into ordered structures, BPOSS-PDI-OH could form nanobelt-shaped single crystals, which may hold potential applications in microelectronics. [ABSTRACT FROM AUTHOR]

Coordination‐driven self‐assembly as a powerful bottom‐up approach has been extensively used to construct multifarious supramolecular architectures with increasing complexity and functionality. Due to the unique cavity structures and precisely controllable dimensions, 3D supramolecules display unprecedented properties and functions in catalysis, sensing, gas storage, and smart materials. Herein, we have built two 3D nanocages with different sizes by changing the length of the organic ligand arms. The structures were characterized by 1D and 2D NMR spectroscopy, electrospray ionization‐mass spectrometry (ESI‐MS), traveling wave ion mobility‐mass spectrometry (TWIM‐MS), gradient tandem‐mass spectrometry (gMS2), and transmission electron microscopy (TEM). Furthermore, the intermolecular dynamic exchange of two 3D nanocages was conducted to construct a series of hybrid 3D structures as evidenced by mass spectrometry. Two 3D nanocages with different sizes are assembled successfully by a stepwise approach. The further dynamic ligand exchange between two preassembled nanocages generated as a series of hybrid supramolecular nanocages, suggesting the remarkable tolerance of such structures with different edge length. The rapid communication between supramolecules via ligand exchange further increased the complexity of the system. [ABSTRACT FROM AUTHOR]

Horizontal assembly of 2D metallomacrocycles is a well‐known strategy for extending ring‐in‐ring planar metallostructures. In their Communication on page 14116 ff., P. Wang, G. R. Newkome et al. report the vertical self‐assembly of double‐ and triple‐decker 3D metallohexagons (depicted as stacked spoked wheels) from multitopic tristerpyridines and Cd2+ ions. Comprising up to 72 ion pairs, the 3D metallohexagons show reversible gelation under thermodynamic conditions. [ABSTRACT FROM AUTHOR]

We demonstrate the reversible micellar aggregation of a DNA-azobenzene conjugate in aqueous conditions, in which the photoisomerization of the initially apolar trans -azobenzene moiety to the polar cis isomer causes disassembly of the aggregates. The molecular basis for this phenomena is a change in the hydrophobic/hydrophilic balance of the conjugate as the more polar cis azobenzene isomer is formed upon exposure to 365 nm irradiation. The conjugates were prepared by copper-free Click chemistry between an azide-modified, 53-base ssDNA and a cyclooctyne derivative of azobenzene. The photocontrolled aggregation of the conjugate was studied by dynamic light scattering and atomic force microscopy. The reversible micellar aggregation for a DNA-azobenzene conjugate has not been previously reported and holds promise for photocontrolled drug delivery applications. [ABSTRACT FROM AUTHOR]