Cu24O24Si8R8: Organic Soluble 56-Membered Copper(I) Siloxane Cage and Its Use in Homogeneous Catalysis

Organic soluble 56-membered copper(I) siloxane cage compound Cu24O24Si8R8 (1, R = (2,6-iPr(2)C(6)H(3))N(SiMe3)) has been synthesized and structurally characterized. It consists of a copper silica-supported structure, in which the metal ions are two-coordinate and covalently anchored onto the cage surface and the weak metal center dot center dot center dot metal d(10)-d(10) interactions are widely full within the cage, that is active in catalyzing the Ullmann-Goldberg-type C-N coupling reaction involving aryl or 2-thienyl bromides with heterocyclic nitrogen nucleophiles. This work provides insight into homogeneous catalysis utilizing the heterogeneous structure.