The kinetics of oxidation of n-propyl and benzyl alcohols by molecular oxygen in the presence of copper- o-phenanthroline complexes and bases at 30 – 70 °C in various solvents was studied. Depending on the reaction conditions (alkalinity of the medium, the solvent used, ligand concentration, temperature, etc.) a catalyst can exist in the form of mono- and/or divalent copper complexes. Cu(I) complexes catalyze the oxidation of primary alcohols to aldehydes with more than 90% selectivity. In the presence of Cu(II) complexes, primary alcohols are oxidized to yield acids. Mechanisms have been suggested, according to which in both cases the oxidation of primary alcohols occurs via the formation of a ternary complex [Cu +n⋯ RO −⋯ O 2], where RO − is an alcoholate ion. The reaction proceeds without free radical participation in the overall mechanism of catalytic oxidation. The reaction involves activation of RO − anions by copper complexes towards molecular oxygen.