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 (BuC)-Bu-t CH as starting materials afforded three new Cu(I) alkynyl complexes, namely, [Cu-14((BuC)-Bu-t C)(10)(NO3)(4)(MeOH)(2)]center dot H2O (1), Cu-15((BuC)-Bu-t C)(14)(NO3) (2), and [Cu-14((BuC)-Bu-t C)(8)(NO3)(2)(CN)(4)](n) (3). Single-crystal X-ray analysis revealed that clusters 1 and 2 consist of Cu-14 and Cu-15 cores costabilized by strong by sigma- and pi-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.