An important problem in designing any large network is the assembly of systems that are resilient to change. From a chemical point of view, an analogy can be used where one requires supramolecular assemblies to maintain their dimensionality combined with limited structural perturbation in response to variation in its intermolecular framework. The identification of hydrogenbonded framework patterns within experimentally known supramolecular assemblies that are structurally robust to disruption and selective hydrogen substitution are envisioned to act as a supramolecular blueprint or template for metal-ion retroinsertion. Here, we report the formation of a large neutral discrete pseudo-spherical coordination capsule assembled from 6 pyrogallol[4]arene ligands and 24 Cu(II) metal ions. Amazingly, this coordination capsule is structurally analogous to its hydrogenbonded counterpart. This result shows a robust ability of pyrogallol[4]arene molecules to self-assemble into large hexameric cage structures from either the hydrogen-bonding or metal-ligand coordination process. The identification of robust supramolecular assemblies that conserve their structure in response to interchangeability between hydrogen-bonded networks for metal coordination, or inversely, represents an important advancement in supramolecular design.coordination ͉ self-assembly ͉ hexamer I nspired by the architectural beauty and robustness found within nature, the design of large multicomponent spheroid cage assemblies on the nanometer scale is becoming increasing feasible. These large supramolecular architectures often resemble and conform to the simple geometrical shapes described by Platonic or Archimedean solids (1). Indeed, such structural morphologies have attracted tremendous interest because of their practical applications for encapsulating various guest molecules (2). Synthetic chemists have principally relied on various self-assembly methods in their construction, such as hydrogen bonds (3) or metal-ligand coordination (4), although some notable covalent methods have recently been reported (5).A popular strategy for designing large multicomponent cage assemblies is the metal-directed self-assembly approach, advocated chiefly by Fujita and coworkers (6-9) and Stang and coworkers (10-12). This method has mainly focused on the geometrical permutation of various triangular pyridine-like bridging ligands driven by coordination to cis-protected Pd metal centers. Nevertheless, for the construction of discrete assemblies with large molecular cavities, the molecular paneling approach by Fujita and coworkers (13) has received the most success. Indeed, an amazingly large discrete functionalized spherical coordination network assembled from 12 metal ions and 24 exo-multidentate ligands was recently reported (14). However, an inherent complication of using n-dimensional pyridine-like spacer multidentate ligands in coordination is the resultant high positive charge combined with porous surfaces within these supramolecular assemblies. The counterions us...

Uncommon water chain: A large neutral hexameric coordination cage [Ga12(H2O)24(C40H42O12)6⊂(acetone)8(H2O)6] is assembled from six pyrogallol[4]arene ligands and twelve GaIII ions. Found within the capsule structure are two pseudo‐linear hydrogen‐bonded water (H2O)5 chains (see picture, Ga gold, O red).

The facile self‐assembly of six pyrogallol[4]arene molecules leads to a globular truncated octahedron, which encapsulates a guest cluster consisting of ethyl acetate and water molecules (see scheme). The interactions between host capsules can be controlled by derivatization of the exterior surface of the capsule.

Large multicomponent nanospheroid arrays consisting of six C-pentylpyrogallol[4]arene molecules and 12 Ga3+ metal-ions which in turn enclose 1150 A3 of chemical space are reported.

Under various conditions, water molecules dramatically affect a number of solid-state C-alkylpyrogallol[4]arene assemblies. In the absence of water, hydrogen-bonded hexameric capsules are formed for the C-butyl, pentyl, hexyl, and heptyl pyrogallol[4]arenes. Introduction of water to acetonitrile solutions containing C-propyl-C-octylpyrogallol[4]arenes resulted in the formation of markedly different bilayer structures and the structural identification of two new dimer-type motifs.