Reactions of dioxygen and Cull) complexes of a series of bis[2-(2-pyridyl)ethyl]amine ligands bearing different phenol groups (2H = N,N-bis [2-(2-pyridyl) ethyl]-2-(3-hydroxyphenyl)ethylamine, 3H = N, N-bis [2-(2-pyridyl)ethyl] tyramine, 4H =N,N-bis[2-(2-pyridyl)ethyl]-2-(2-hydroxy-5-methylphenyl)ethylamine have been investigated to obtain insight into the reactivity of copper-active oxygen complexes toward phenols. Treatment of [Cu-I(2H)](PF6) and [Cu-I(3H)](PF6) with O-2 resulted in the benzylic ligand hydroxylation in 9 and 14%, respectively, together with formation of polymeric products, while the reaction of [Cu-I(4H)](PF6) and O-2 gave a dinuclear phenolate copper(ll) complex, [CU2II(4(-))(2)](2+), and H2O2 The structure and reactivity of the active oxygen intermediates are discussed.