Assembly of Cu(I) Alkynyl Complexes: From Cluster to Infinite Cluster-Based Framework

Variation of the reaction conditions with Cu powder, Cu­(NO3)2, and t BuCCH as starting materials afforded three new Cu­(I) alkynyl complexes, namely, [Cu14( t BuCC)10­(NO3)4­(MeOH)2]­·H2O (1), Cu15( t BuCC)14­(NO3) (2), and [Cu14( t BuCC)8­(NO3)2­(CN)4] n (3). Single-crystal X-ray analysis revealed that clusters 1 and 2 consist of Cu14 and Cu15 cores costabilized by strong by σ- and π-bonded tert-butylethynides and nitrates. Complex 3 displays an intriguing three-dimensional cyano-bridged Cu­(I) alkynyl cluster-based framework, in which the existence of CN– is assumed to have originated from the Cu­(I)-mediated C–C cleavage reaction of acetonitrile under mild solvothermal conditions.