Isolation and Structural Elucidation of 15‐Nuclear Copper Dihydride Clusters: An Intermediate in the Formation of a Two‐Electron Copper Superatom

Highly reactive copper‐dihydride clusters, [Cu15(H)2(S2CNR2)6(C2Ph)6](PF6) {R = nBu (1H), nPr (2H), iBu (3H)}, are isolated during the reaction of [Cu28H15{S2CNnBu2}12](PF6) with ten equivalents of phenylacetylene. They are found to be intermediates in the formation of the earlier reported two‐electron superatom [Cu13(S2CNR2)6(C2Ph)4]+. Better yields are obtained by reacting dithiocarbamate sodium salts, [Cu(CH3CN)4](PF6), BH4− and phenylacetylene. The presence of two hydrides in the isolated clusters is confirmed by the synthesis and characterization of its deuteride analogue [Cu15(D)2(S2CNR2)6(C2Ph)6]+, and a single‐crystal neutron structure of 2H. Structural characterization of 1H reveals a new bicapped icosahedral copper(I) cage encapsulating a linear copper dihydride (CuH2)− unit. Reaction of 3H with Au(I) salts yields a highly luminescent [AuCu12(S2CNiBu2)6(C2Ph)4]+ cluster. A 15‐nuclear copper dihydride cluster [Cu15(H)2(S2CNR2)6(C2Ph)6](PF6) (1) containing a linear [CuH2]− complex embedded in a [Cu14]14+ cage is isolated and structurally characterized. This cluster readily converts to a two‐electron superatom cluster [Cu13]11+ at elevated temperatures. Highly luminescent [AuCu12(S2CNR2)6(C2Ph)4]+ cluster is isolated by reacting 1 with Au(I) salts.