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Metal‐metal bonds have rarely been explored as active elements in supramolecular assemblies despite their unique potential to introduce responsive behavior. In this report, a dynamic molecular container composed of two cyclometalated Pt units is constructed using Pt−Pt bonds. This molecule—the flytrap—has a flexible jaw composed of two [18]crown‐6 ethers that can adapt their shape to bind large inorganic cations with sub‐micromolar affinity. Along with the spectroscopic and crystallographic characterization of the flytrap, we report its photochemical assembly, which allows the capture of ions and their transport from solution to the solid state. In addition, we have been able to recycle the flytrap to regenerate its starting material due to the reversible nature of the Pt−Pt bond. We believe that other molecular containers and materials for harvesting valuable substrates from solution could be assembled using the advances presented here. [ABSTRACT FROM AUTHOR]

Macrocycle engineering is a key topic in supramolecular chemistry. When synthesizing a ring, one can obtain either complex mixtures of macrocycles of different sizes or a single ring if a template is utilized. Here, we unite these approaches along with post‐synthetic modifications to transform a single tether into multiple rings—up to five per tether. The macrocycles contain two bridged phenylpyridine ligands that are connected through a Pt atom, which defines the rings' shape, size, and host activity. All rings undergo redox reactions (between PtII and PtIV) that allow for large conformational changes. Their reactivity, together with their host performance, is a convenient way to control the capture and release of guests, to mediate ring transformations, and to control pseudorotaxane‐to‐pseudorotaxane conversions. This novel approach could serve to assemble other libraries of small ring molecules, create cyclic polymers bridged by responsive‐at‐metal nodes, and produce processable mechanically interlocked molecules. [ABSTRACT FROM AUTHOR]

Abstract: A novel pyrene‐substituted thioethyl‐porphyrazine (PzPy) and the formation of supramolecular assembly with nanocarbons demonstrating photoinduced electron transfer ability are designed. As revealed by spectroscopic and electrochemical studies, PzPy displays wide spectral absorption in the visible range, charge separation upon photoexcitation, as well as bandgap and highest occupied/lowest unoccupied molecular orbital (HOMO/LUMO) energy values, matching the key requirements of organic optoelectronic. Moreover, the presence of a pyrene moiety promotes attractive interactions with π‐conjugated systems. In particular, theoretical calculations show that in the PzPy the HOMO and LUMO are localized on different positions of the molecule, i.e., the HOMO on the pyrene moiety and the LUMO on the macrocycle. Therefore, HOMO–LUMO excitation gives rise to a charge separation, preventing excitons recombination. Two kinds of noncovalent hybrid composites are prepared by mixing the PzPy with single‐wall carbon nanotubes (SWNTs) and graphene nanoflakes (GNFs), respectively, and used for photocurrent generation through charge transfer processes between PzPy and nanocarbons. Photoconduction experiments show photocurrent generation upon visible light irradiation of both PzPy/SWNT and PzPy/GNF composites (0.78 and 0.71 mA W−1 at 500 nm, respectively), demonstrating their suitability for optoelectronic applications and light harvesting systems. [ABSTRACT FROM AUTHOR]

In their Communication (e202305525), Mark J. MacLachlan use a single Pt-Pt bond to glue two cyclometalated hosts together and generate a flytrap-like molecule. Keywords: Host-Guest Chemistry; Metal-Metal Bonding; Platinum; Redox; Supramolecular Chemistry EN Host-Guest Chemistry Metal-Metal Bonding Platinum Redox Supramolecular Chemistry 1 1 1 07/21/23 20230724 NES 230724 B Supramolecular Chemistry b . This compound traps inorganic ions, assembles and disassembles photochemically, and irreversibly transports guests from solution to the solid state. [Extracted from the article]

Post‐synthetic modification of mechanically interlocked molecules (MIMs) is an attractive avenue to add complexity to already intricate systems. This remains an important, challenging topic that is under‐developed. In this paper, we report the synthesis and characterization of a [2]rotaxane molecule featuring a ring appended to an emissive cyclometalated PtII unit. Modulation of the oxidation state at the metal center can transform the interlocked molecule into a new PtIV [2]rotaxane or a PtIII [3]rotaxane held together by an intermetallic Pt−Pt bond – a first of its kind. These molecules display distinct structural and photophysical properties, as well as shuttling dynamics. This approach for post‐synthetic modification could be used to construct more complex MIMs and inorganic supramolecular assemblies with redox properties. [ABSTRACT FROM AUTHOR]

The supramolecular chemistry of bowl-shaped heptazinc metallocavitands templated by Schiff base macrocycles has been investigated. Dimerization thermodynamics were probed by 1H NMR spectroscopy in benzene-d& toluene-d5, and pxylene-d60 and revealed the process to be entropy-driven and enthalpy-opposed in each solvent. Trends in the experimentally determined enthalpy and entropy values are related to the thermodynamics of solvent autosolvation, Solvent molecules being released from the monomeric metallocavitand cavity into the bulk solvent upon dimerization. The relationship established between experimentally measured dimerization thermodynamics and autosolvation data successfully predicts the absence of dimerization in CH1CI2 and CHCI5 and was used to estimate the number of solvent molecules interacting with the monomeric metallocavitand in solution. Host-guest interactions between heptazinc metallocavitands and fisilerene C60 have also been investigated. Interestingly, metallocavitand-Cw interactions are only observed in solvents that facilitate entropy-driven dimerization suggesting entropy and solvent autosolvation may be important in explaining concave-convex interactions. [ABSTRACT FROM AUTHOR]

Abstract: Halogen bonding (XB) has been recently exploited as a significant tool for engineering crystals involving coordination and organometallic compounds as tectons. This review, in particular, focuses on extended networks based on XB between electron donor groups bound to metals and halo-pyridine and halo-tetrathiafulvalene moieties as electron acceptors. The influence of XB over the structures and the interactions between the organic frameworks and the metal centers is highlighted. The chemistry of some mononuclear systems forming XB is described in terms of tools for controlling supramolecular arrangement and chemical behaviour. Various computational studies on the energy of XB at different levels of sophistication, their advantages and limits concerning the evaluation of the interaction energy and modelling of its origin are critically surveyed. Modelling of a new example of interaction between Cp2MH2 (M=Mo, W) and CF3I is reported together with the description of the electron density of the complex analyzed in terms of the Quantum Theory of Atoms in Molecules (QTAIM) model. [Copyright &y& Elsevier]