A modular approach for the synthesis of cage structures is described. Reactions of [(arene)RuCl(2)](2) [arene = p-cymene, 1,3,5-C(6)H(3)Me(3), 1,3,5-C(6)H(3)(i-Pr)(3)] with formyl-substituted 3-hydroxy-2-pyridone ligands provide trinuclear metallamacrocycles with pendant aldehyde groups. Subsequent condensation reactions with di- and triamines give molecular cages with 3, 6, or 12 Ru centers in a diastereoselective and chemoselective (self-sorting) fashion. Some of the cages can also be prepared in one-pot reactions by mixing [(arene)RuCl(2)](2) with the pyridone ligand and the amine in the presence of base. The cages were comprehensively analyzed by X-ray crystallography. The diameter of the largest dodecanuclear complex is ∼3 nm; the cavity sizes range from 290 to 740 Å(3). An amine exchange process with ethylenediamine allows the clean conversion of a dodecanuclear cage into a hexanuclear cage without disruption of the metallamacrocyclic structures.

The synthesis of topologically complex structures, such as links and knots, is one of the current challenges in supramolecular chemistry. The so-called Solomon link consists of two doubly interlocked rings. Despite being a rather simple link from a topological point of view, only few molecular versions of this link have been described so far. Here, we report the quantitative synthesis of a giant molecular Solomon link from 30 subcomponents. The highly charged structure is formed by assembly of 12 cis-blocked Pt(2+) complexes, six Cu(+) ions, and 12 rigid N-donor ligands. Each of the two interlocked rings is composed of six repeating Pt(ligand) units, while the six Cu(+) ions connect the two rings. With a molecular weight of nearly 12 kDa and a diameter of 44.2 Å, this complex is the largest non-DNA-based Solomon link described so far. Furthermore, it represents a molecular version of a "stick link".

The facile synthesis of anionic bipyridyl ligands with dinuclear clathrochelate cores is described. These metalloligands can be obtained in high yields by the reactions of M(ClO 4 ) 2 (H 2 O) 6 (M: Zn, Mn, or Co) with 4-pyridylboronic acid and 2,6-diformyl-4-methylphenol oxime or 2,6-diformyl-4-tert-butylphenol oxime, followed by deprotonation.The ligands are interesting building blocks for metallasupramolecular chemistry, as evidenced by the formation of a Ptbased molecular square and four coordination polymers with 2D or 3D network structures. Competition experiments reveal that the utilization of anionic bipyridyl ligands can result in significantly more stable assemblies.

The synthesis of a cylindrical, imine-based cage composed of two trimeric metallamacrocycles is described. The cage acts as a heterotopic receptor for alkali metal cations. The small cations Li(+), Na(+), and K(+) bind to the outside of the cage with good selectivity for Li(+), whereas the larger cations Rb(+) and Cs(+) are bound inside the cage to form unusual π complexes with a good selectivity for Cs(+). Negative heterotopic cooperativity between the two binding sites is observed. The complexation of Cs(+) is associated with a color change, which enables the cage to be used as a specific sensor for Cs(+).

The synthesis of topologically complex structures, such as links and knots, is one of the current challenges in supramolecular chemistry. The so‐called Solomon link consists of two doubly interlocked rings. Despite being a rather simple link from a topological point of view, only few molecular versions of this link have been described so far. Here, we report the quantitative synthesis of a giant molecular Solomon link from 30 subcomponents. The highly charged structure is formed by assembly of 12 cis‐blocked Pt2+ complexes, six Cu+ ions, and 12 rigid N‐donor ligands. Each of the two interlocked rings is composed of six repeating Pt(ligand) units, while the six Cu+ ions connect the two rings. With a molecular weight of nearly 12 kDa and a diameter of 44.2 Å, this complex is the largest non‐DNA‐based Solomon link described so far. Furthermore, it represents a molecular version of a “stick link”.