Syntheses and Structure Determination of Trimethylsiloxy Functionalized Copper Chalcogenide Clusters

Four new copper chalcogenide clusters with trimethylsiloxy groups in the ligand shell have been synthesized and characterized by single‐crystal X‐ray diffraction. The compounds [Cu 22 Se 6 (S‐C 6 H 4 ‐OSiMe 3 ) 10 (PPh 3 ) 8 ] ( 1 ), [Cu 36 Se 8 (S‐C 6 H 4 ‐OSiMe 3 ) 20 (PPh 3 ) 8 ] ( 2 ) and [Cu 52 Se 20 (S‐C 6 H 4 ‐OSiMe 3 ) 12 (PPh 3 ) 11 ] ( 3 ) are core‐shell ‐cluster, in which the heavy atom frameworks are built up of a copper selenide core which is partly surrounded by a copper thiolate shell. They were synthesized by the reaction of CuOAc and PPh 3 with p ‐Me 3 SiS‐C 6 H 4 ‐OSiMe 3 and Se(SiMe 3 ) 2 in different ratios. The arrangements of the chalcogen atoms in 1 and 2 are similar to a close packing, while cluster 3 has a new unusual structural motif. In addition the analogous precursor p ‐Me 3 SiSe‐C 6 H 4 ‐OSiMe 3 was synthesized and investigated in the cluster synthesis. The reaction with CuOAc, PPh 3 and Se(SiMe 3 ) 2 leads to the formation of the functionalized copper selenide cluster [Cu 22 Se 6 (Se‐C 6 H 4 ‐OSiMe 3 ) 10 (PPh 3 ) 8 ] ( 4 ). This compound is similar to 1 and consists of a Cu 22 Se 16 core instead of a Cu 22 Se 6 S 10 core. The functionalization of the cluster compounds with trimethylsiloxy‐groups leads to a high solubility of these cluster.