Catalytic Activity of Copper(II)-Ethylenediamine Complexes in Autoxidation of Phenols

Article abstract of DOI:10.1021/jo00173a033

Studies of the autoxidation of tert-butylphenols 1-4 with molecular oxygen in the presence of Cu(II) complexes of N-substituted ethylenediamines indicate that the most catalytically active complexes are sterically crowded around the nitrogen atoms.The principal primary oxidation products formed in the presence of these complexes are substituted biphenyls 5, 7, 10, and 14, the first three of which are converted into secondary products on prolonged oxidation.Only in the oxidation of 2 is a diphenyl ether (9) formed, in quantities that increase little after the first 5 min of oxidation.