Mercaptothiacalixarenes Steer 24 Copper(I) Centers to form a Hollow‐Sphere Structure Featuring Cu2S2 Motifs with Exceptionally Short Cu⋅⋅⋅Cu Distances

Tetramercaptotetrathiacalix[4]arene ( LH₄ ) can be used as a coordination platform to bind four Cu^I ions at the thiolate and thioether S atoms. Donor ligands such as phosphanes can stabilize the resulting [LCu₄] units, which then remain monomeric ( [(Ph₃PCu)₄L] ). In the absence of donor ligands, they aggregate, providing a hexamer ( [LCu₄]₆ ) in high yields, with a hollow‐sphere structure formed by an unprecedented Cu₂₄S₄₈ 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.