Mercaptothiacalixarenes Steer 24 Copper(I) Centers to form a Hollow-Sphere Structure Featuring Cu S Motifs with Exceptionally Short Cu⋅⋅⋅Cu Distances.

Tetramercaptotetrathiacalix[4]arene (LH ) can be used as a coordination platform to bind four Cu ions at the thiolate and thioether S atoms. Donor ligands such as phosphanes can stabilize the resulting [LCu ] units, which then remain monomeric ([(Ph PCu) L]). In the absence of donor ligands, they aggregate, providing a hexamer ([LCu ] ) in high yields, with a hollow-sphere structure formed by an unprecedented Cu S cage that is surrounded by the organic framework of the calixarene chalices. Preliminary NMR experiments with regard to the host-guest chemistry in solution showed that the compound represents a polytopic host for acetonitrile and methane.