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, Cu (H) (S CNR ) (C Ph) {R = Bu (1 ), Pr (2 ), Bu (3 )}, are isolated during the reaction of Cu H {S CN Bu } with ten equivalents of phenylacetylene. They are found to be intermediates in the formation of the earlier reported two-electron superatom [Cu (S CNR ) (C Ph) ] . Better yields are obtained by reacting dithiocarbamate sodium salts, Cu(CH CN) , BH and phenylacetylene. The presence of two hydrides in the isolated clusters is confirmed by the synthesis and characterization of its deuteride analogue [Cu (D) (S CNR ) (C Ph) ] , and a single-crystal neutron structure of 2 . Structural characterization of 1 reveals a new bicapped icosahedral copper(I) cage encapsulating a linear copper dihydride (CuH ) unit. Reaction of 3 with Au(I) salts yields a highly luminescent [AuCu (S CN Bu ) (C Ph) ] cluster.