Aromatic Hydroxylation Reactivity of a Mononuclear Cu(II)−Alkylperoxo Complex

Reaction of copper(II) complex 1 X supported by the tridentate bis(pyridylmethyl)amine ligand containing m -substituted phenyl groups at the 6-positions of the pyridine rings (L X ) with H 2 O 2 in the presence of triethylamine (NEt 3 ) in acetone generates a copper(II)−alkylperoxo species 2 X [2-hydroxy-2-hydroperoxypropane (HHPP) adduct]. The alkylperoxo intermediate 2 X undergoes an efficient aromatic ligand hydroxylation reaction, producing a phenolate complex 4 X via another intermediate 3 X . Kinetic studies on the aromatic hydroxylation process are reported together with spectral characterization of 2 X .