We have synthesized an asymmetric dinucleating ligand connecting the N-3 and N-4 coordination sites with an amido linkage and characterized the corresponding dicopper(l) complex by spectroscopic methods. The dicopper(I) complex reacted with O-2 at low temperature to yield a (mu-peroxo)Cu-2 species with a mu-eta(1):eta(2)-binding mode. We also explored an effect of this amide linkage that contributed to stabilizing a mu-eta(1):eta(2)-Cu2O2 adduct.