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Abstract We describe here an unorthodox approach to dynamic covalent chemistry in which the initially-unexpected in-situ hydrolysis of a bis-imide is employed to control the composition of a library of structurally diverse macrocycles. A single building block is used to generate a library of numerous disulfide-based architectures in a one-pot single-step process. The dual-stimuli method is based on simultaneous changes in pH and DMSO concentration to expand the structural diversity of the macrocyclic products. Mechanistic details of this complex process are investigated by the kinetics analysis. We delivered a facile strategy for the synthesis of water-soluble, multicomponent and dynamic macrocycles equipped with number of different functional groups, thus giving a prospect of their application in guest-driven phase transfer.

Four complexes of different Cd(II) salts with 6,6″-dimethyl-2,2′:6′,2″-terpyridine L have been synthesized of the following structural formulae: [CdL(CH3OH)(ClO4)2] (1) [CdL(Cl/Br)2] (2) [CdLCl2] (2a) [CdL(CH3CO2)2] (3). Their properties have been established through analytical and spectroscopic (ESI-MS, IR, 1H NMR and UV–Visible absorption and emission) methods as well as by X-ray structure determinations. Quite high quantum yield values were obtained for the solution luminescence, despite the fact that presented compounds are ‘open species’ i.e. are susceptible to the effect of external environment. Titration experiments proved speciation i.e. formation of both 2:1 and 1:1 (L:Cd2+) species in MeCN, yet only the latter ones can be isolated in their crystalline form. In the solid state, there appears to be a correlation between the emission intensity and the stacking arrays in the lattice. There is no evidence that the methyl substituents exert a major influence upon the properties of the complexes, and it is implied however that they might also be responsible for preferential formation of 1:1 complexes in the solid state due to observed intermolecular packing lattices. Keywords: Terpyridine, Cadmium complexes, Luminescent materials, Hirshfeld surfaces, Self-assembly

An Ag(I) metallacycle obtained unexpectedly during the preparation of Pd(II) complexes of the bifunctional ligand 5-([2,2′-bipyridin]-5-yl)pyrimidine-2-amine (L) has been characterized using X-ray structure determination as a binuclear, metallacyclic species [Ag2L2](SbF6)2, where both the bipyridine and pyrimidine-N donors of L are involved in coordination to the metal. The full coordination environment of the Ag(I) defines a case of highly irregular 4-coordination. In the crystal, the Ag-metallacycles assemble into one-dimensional supramolecular metalladynamers linked together by hydrogen-bonding interactions.

Individual hydrogen bonds are weak, so self-assembling multiple components via hydrogen bonding is a significant challenge. Here the authors report a robust, enantiopure nanocapsule held together by 48 cooperative hydrogen bonds, and use it for the selective binding of C70.

Abstract Noncovalent self‐assembly creates an effective route to highly sophisticated supramolecular polymers with tunable properties. However, the outcome of this assembly process is highly dependent on external conditions. In this work, a monomeric naphthalene diimide (NDI), designed to allow solubility in a wide range of solvents, can assemble into three distinct noncovalent supramolecular species depending on solvent composition and temperature. Namely, while the self‐assembly in chlorinated solvents yields relatively short, hydrogen‐bonded nanotubes, the reduction of solvent polarity changes the assembly outcome, yielding π–π stacking polymers, which can further bundle into a more complex aggregate. The obtained polymers differ not only in their global morphology but—more strikingly—also in the thermodynamics and kinetics of their supramolecular self‐assembly, involving isodesmic or two‐stage cooperative assembly with kinetic hysteresis, respectively. Ultimately, three distinct assembly states can be accessed in a single experiment.

We previously reported novel fluorescent aromatic cages that are self-produced using a set of orthogonal dynamic covalent reactions, operating simultaneously in one-pot, to assemble up to 10 components through 12 reactions into a single cage-type structure. We now introduce N-functionalized amino acids as new building blocks that enable tuning the solubility and analysis of the resulting cages. A convenient divergent synthetic approach was developed to tether different side chains on the N-terminal of a cysteine-derived building block. Our studies show that this chemical functionalization does not prevent the subsequent self-assembly and effective formation of desired cages. While the originally described cages required 94% DMSO, the new ones bearing hydrophobic side chains were found soluble in organic solvents (up to 75% CHCl3), and those grafted with hydrophilic side chains were soluble in water (up to 75% H2O). Fluorescence studies confirmed that despite cage functionalization the aggregation-induced emission properties of those architectures are retained. Thus, this work significantly expands the range of solvents in which these self-assembled cage compounds can be generated, which in turn should enable new applications, possibly as fluorescent sensors.