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We have developed a tunable emissive supramolecular metallo-gel functionalized with lanthanide coordination bonds using a low molecular weight gelator 1 having terminal terpyridine. In the presence of Tb(III) and Eu(III) ions, the coordination of lanthanides to gelator 1 results in green and red emissive supramolecular metallogels, respectively. A supramolecular growth mechanism of 1-Tb that follows an isodesmic model has been observed, relying on delicate balances between non-covalent interactions. Furthermore, controlling the stoichiometry of lanthanide metal ions with respect to 1 : Tb(III) : Eu(III) leads to yellow and white light-emitting supramolecular bimetallic gels. [ABSTRACT FROM AUTHOR]

We report Ag(I)-coordinated supramolecular architectures of a terpyridine-based ligand bearing an alanine moiety and a trans- or cis-double bond in the alkyl chain in the presence of AgNO3 (0.5 and 1.0 equiv.) in H2O and dimethyl sulfoxide (DMSO) (1 : 4 v/v). In the presence of AgNO3, trans-L exhibited a helical ribbon structure while cis-L exhibited a linear ribbon structure. Furthermore, self-assembled trans-L exhibited a strong circular dichroism (CD) signal helicity. In contrast, self-assembled cis-L formed in the presence of 0.5 and 1.0 equiv. of AgNO3 showed a weak CD signal, indicating that the cis-L molecules did not form a helical arrangement in the supramolecular architecture. [ABSTRACT FROM AUTHOR]

The initial evaluation of MOF entanglements as their main limitation is changing to an opportunity since the related benefits are now known. Based on a linear rigid dicarboxylic acid, biphenyl-4,4′-dicarboxylic acid (H2bpdc), and a flexible dipyridyl piperazine ligand, 1,4-bis(4-pyridylmethyl)piperazine (bpmp), with versatile conformations, four divalent metal–organic frameworks (MOFs), namely {[Cu2(bpmp)2(bpdc)2(H2O)2]·1.25DMF·1.5H2O}n (1), {[Zn2(bpmp)(bpdc)2]·2H2O}n (2), {[Cd(bpmp)(bpdc)(H2O)2]·2DMA}n (3), and [Cd(bpmp)1.5(bpdc)]n (4), with entangled structures from interpenetration and self-penetration to polycatenation are reported. In all the products, both bpmp and bpdc acted as linkers, connecting the metal centres into different entangled frameworks: 3D inclined polycatenane (1), 4-fold interpenetrated 3D MOF with the pcu topology (2), non-interpenetrated square net 2D MOF with sql topology (3), and self-penetrated 3D MOF (4). The solvent-dependent formations of Cd-MOFs 3 and 4 are discussed in detail as 3 isolated from DMA/water is a simple square net product, while 4 obtained from DMF/water shows a self-penetrating 3D framework in which three square circuits are interlocked with each other to form a cyclic [3]catenane unit via threading of the S-shaped bpmp. These cyclic [3]catenanes were further linked by the V-shaped bpmp, giving rise to a 3D infinite aggregate of cyclic [3]catenanes via the self-penetration, which seems to be unique. Consequently, all the products shared a square net (or square circuit) layer, which was further extended and interlocked in different ways depending on the conformations and roles of the flexible ligands together with the ligand–ligand or ligand–solvent interactions. The photoluminescence properties of the products were compared with those of free ligands and discussed. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) with tunable chirality is currently a challenging issue in the development of supramolecular nanomaterials. We herein report the formation of helical nanoribbons which grow into helical tubes through dynamic helicity inversion. For this, chiral PtII complexes of terpyridine derivatives, namely S‐trans‐1 and R‐trans‐1, with respective S‐ and R‐alanine subunits and incorporating trans‐double bonds in the alkyl chain were prepared. In DMSO/H2O (5 : 1 v/v), S‐trans‐1 initially forms a fibrous self‐assembled product, which then undergoes dynamic transformation into helical tubes (left‐handed or M‐type) through helical ribbons (right‐handed or P‐type). Interestingly, both helical supramolecular architectures are capable of emitting CPL signals. The metastable helical ribbons show CPL signals (glum=±4.7×10−2) at 570 nm. Meanwhile, the nanotubes, which are the thermodynamic products, show intense CPL signals (glum=±5.6×10−2) at 610 nm accompanied by helicity inversion. This study provides an efficient way to develop highly dissymmetric CPL nanomaterials by regulating the morphology of metallosupramolecular architectures. [ABSTRACT FROM AUTHOR]